豊田　剛己TOYODA Kokiトヨダ　コウキ

業績情報

氏名・連絡先

• 氏名

  トヨダ　コウキ, 豊田　剛己, TOYODA Koki

• Fax番号

  042-388-7915

• eメールアドレス

  kokitcc.tuat.ac.jp

• 個人ホームページ

  http://www.tuat.ac.jp/~toyoda/

主たる所属・職名

• 農学研究院　生物システム科学部門, 教授

その他の所属

• 生物システム応用科学府　食料エネルギーシステム科学専攻

学歴

• 名古屋大学
  農学部
  農芸科学科
  至 1988年, 卒業
• 名古屋大学
  農学研究科
  至 1990年, 修了, 博士前期
• 名古屋大学
  農学研究科
  至 1993年, 修了, 博士後期

学位

• 博士（農学）

教育・研究活動状況

• 　世界の人口が60億人を突破しました。地球温暖化、砂漠化、土壌劣化等の地球規模の環境問題を考慮しつつ、 増え続ける人口を支えるには、持続的で、低投入な農業生産システムの確立・向上が望まれます。生産 という収奪を必然的に伴う農業において持続的農業を維持するためには、堆厩肥等何らかの有機物を施用 することが必要不可欠です。有機物連用土壌を一つのシステムと捉え、微生物、原生動物、土壌動物を含 めた（微）生物間相互作用を明らかにし、（微）生物的側面からシステム内の安定性、生産性について考 えていくことを計画しています。現在、土壌病害は作物生産に少なからず影響を及ぼしている一方、病気 の発生が少ない発病抑止型土壌の存在が知られています。安定した持続的農業を維持するには病害による 被害を最小限に抑えることが要求されることから、発病抑止型土壌の抑止機構の解明に取り組みたいと思 っています。土壌の有する”すばらしい”機能について、微生物学的、生態学的、環境化学的に明らかに し、持続的生物生産システムを確立する上での碑となる基礎データを蓄積していきたいと考えています。

研究分野

• A189　ライフサイエンス, A38010　植物栄養学、土壌学

研究テーマ

• 土壌中における微生物の生態に関する研究
  自 9999

科学研究費助成事業

• 挑戦的研究（開拓）
  持続的農業システムのための食料生産プロセス工学の開拓
  自 2020年, 至 2020年
• 挑戦的研究（開拓）
  持続的農業システムのための食料生産プロセス工学の開拓
  自 2019年, 至 2019年
• 挑戦的研究（開拓）
  持続的農業システムのための食料生産プロセス工学の開拓
  自 2018年, 至 2018年
• 基盤研究(B)
  富栄養化精密予測に向けた土壌コロイド粒子に存在するリンの化学形態と生物利用の連関
  自 2018年, 至 2018年
• 基盤研究(C)特設分野研究
  有機栽培土壌における銅・亜鉛の過剰蓄積と抗生物質耐性菌の食料・環境影響
  自 2017年, 至 2017年
• 基盤研究(B)
  富栄養化精密予測に向けた土壌コロイド粒子に存在するリンの化学形態と生物利用の連関
  自 2017年, 至 2017年
• 基盤研究(B)海外学術調査
  世界最大のゴマ生産国ミャンマーにおけるゴマの線虫害の実態調査と防除法の開発
  自 2016年, 至 2019年
• 挑戦的萌芽研究
  原子レベルの化学状態解析に基づく（ナノ）タングステンの土壌中での挙動・毒性解明
  自 2016年, 至 2016年
• 基盤研究(C)
  有機栽培土壌における銅・亜鉛の過剰蓄積と抗生物質耐性菌の食料・環境影響
  自 2016年, 至 2016年
• 基盤研究(B)
  富栄養化精密予測に向けた土壌コロイド粒子に存在するリンの化学形態と生物利用の連関
  自 2016年, 至 2016年
• 基盤研究(C)特設分野研究
  有機栽培土壌における銅・亜鉛の過剰蓄積と抗生物質耐性菌の食料・環境影響
  自 2015年, 至 2015年
• 挑戦的萌芽研究
  原子レベルの化学状態解析に基づく（ナノ）タングステンの土壌中での挙動・毒性解明
  自 2015年, 至 2015年
• 基盤研究(B)
  富栄養化精密予測に向けた土壌コロイド粒子に存在するリンの化学形態と生物利用の連関
  自 2015年, 至 2015年
• 挑戦的萌芽研究
  原子レベルの化学状態解析に基づく（ナノ）タングステンの土壌中での挙動・毒性解明
  自 2014年, 至 2014年
• 基盤研究(B)
  ミャンマー国の主要な農作物における植物寄生性線虫の生息状況と被害度調査
  自 2011年, 至 2014年
• 基盤研究(B)
  ミャンマー国の主要な農作物における植物寄生性線虫の生息状況と被害度調査
  自 2011年, 至 2014年
• 基盤研究(C)
  もやし残渣を活用したダイズシストセンチュウ防除法の開発
  自 2010年, 至 2012年
• 基盤研究(A)
  飼料イネを用いた資源循環型の生産および環境修復システムの構築
  自 2010年, 至 2010年
• 基盤研究(A)
  飼料イネを用いた資源循環型の生産および環境修復システムの構築
  自 2009年, 至 2009年
• 基盤研究(A)
  飼料イネを用いた資源循環型の生産および環境修復システムの構築
  自 2008年, 至 2008年
• 基盤研究(B)一般
  ゲノム情報に基づいた線虫病害診断技術の開発　　　　　　　　　　　　　　　　　　　
  自 2005年, 至 2007年
• 基盤研究(A)一般
  水田生態系ビオトープにおける物質循環に関するプロジェクト研究
  自 2001年, 至 2003年
• 若手研究(B)
  堆厩肥連用土壌のトマト青枯病抑制機構の解明
  自 2001年, 至 2002年
• 基盤研究(A)一般
  環境中に微量存在する農薬等の化学物質の土壌生態系に及ぼす影響評価法の開発
  自 2000年, 至 2001年

論文

• Conversion from natural coniferous forests to cedar plantations increase soil nitrogen cycling through changing microbial community structures
  Sawada, Kozue; Inagaki, Yoshiyuki; Sugihara, Soh; Kunito, Takashi; Murase, Jun; Toyota, Koki; Funakawa, Shinya
  APPLIED SOIL ECOLOGY
  ELSEVIER
  Converting natural forests to coniferous plantations in temperate regions often impact soil nitrogen (N) cycling. However, belowground microbial communities responsible for these changes in N cycling are not well understood, particularly in forest ecosystems dominated by coniferous trees. Additionally, the influence of different soil acidity levels on these microbial community changes and their effect on N cycling have not been thoroughly investigated. In order to gain a deeper understanding of these impacts, we conducted a study to examine the effects of the conversion from natural forests dominated by coniferous trees to pure cedar plantations on soil N cycling, as well as the root-associated and soil microbial communities using high-throughput amplicon sequencing technique in two areas with different acidity levels. Our results showed that the conversion increased inorganic N content (i.e., the sum of ammonium and nitrate N), accompanied by a decrease in the relative abundances of ectomycorrhizal fungi and an increase in saprotrophic fungi within class Leotiomycetes regardless of acidity. Additionally, the conversion increased nitrate N content only in the less acidic area (pH about 5.5) but not in the more acidic area (pH below 5). Relative abundances of copiotrophic bacteria, including Burkholderia sp. and Bradyrhizobiaceae, which are enriched in roots, were significantly lower in cedar plantations than in natural forests. These copiotrophic bacteria were significantly lower in the less acidic area than in the more acidic area. The relative abundances of these copiotrophic bacteria were negatively correlated with ammoniaoxidizing archaeal abundances, leading to higher nitrate N content in cedar plantations in the less acidic area. Our findings have practical implications, suggesting that retaining natural forests dominated by ectomycorrhizalassociated coniferous trees and introducing these types of trees into pure cedar plantations may be an effective strategy for reducing nitrate production, particularly in less acidic areas.
  2023年11月, 研究論文（学術雑誌）, 共同, 191, 0929-1393, DOI(公開)(r-map)
• Evaluation of Soil Suppressiveness of Various Japanese Soils against the Soybean Cyst Nematode Heterodera glycines and Its Relation with the Soil Chemical and Biological Properties
  Yang, Yanyan; Wu, Junnan; Perry, Roland N.; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  This study aimed to evaluate the suppressive potential of different soils on soybean cyst nematodes (SCN) and to estimate the suppressive mechanism. Fifteen soils (designated as soil A to O) from different agricultural fields with varying organic inputs were added with SCN-infested soil and grown with a green soybean variety. The SCN density in the soil at 6 weeks of soybean growth was markedly different depending on the soils used, indicating a different level of disease suppressiveness. No significant correlation was observed between the SCN density and any of the soil physicochemical and biological characteristics tested. Then, to estimate a suppression mechanism, F-soil that showed the lowest density of SCN was added to the SCN-infested soil with or without streptomycin to kill bacteria and grown with soybean. SCN density was not increased by the addition of streptomycin, indicating that soil bacteria may not be involved in the suppressiveness of F-soil. In total, 128 fungal strains were isolated from the rhizosphere of F-soil and inoculated in a combination or singly in the SCN-infested soil. After repeated screenings, five strains were selected since the SCN density was consistently decreased by them. Sequence analysis showed that they were closest to Clonostachys rosea, Aspergillus niger, Aspergillus fumigatus, Fusarium oxysporum, and Cylindrodendrum alicantinum. All five strains significantly reduced the mobility of second-stage juveniles (J2). Further, C. rosea a2, A. niger a8, and F. oxysporum a25 significantly decreased hatching. Overall, the present study demonstrated that soil fungi played an important role in SCN suppression in F-soil.
  2023年11月, 研究論文（学術雑誌）, 共同, 13, 11, DOI(公開)(r-map)
• Geographical distribution and phylogenic relationships of Hirschmanniella diversa Sher (Nematoda: Pratylenchidae) in Japan
  Takagi, Motonori; Sekimoto, Shigeyuki; Mizukubo, Takayuki; Wari, David; Akiba, Mitsuteru; Perry, Roland N.; Toyota, Koki
  NEMATOLOGY
  BRILL
  Hirschmanniella diversa and H. imamuri parasitise the lotus, Nelumbo nucifera. Hirschmanniella spp. are the most important pests of lotus cultivation in Japan, but the distribution and species dominancy are not fully understood. In this study, we aimed to collect Hirschmanniella spp. individuals from lotus roots in the major lotus cultivation areas in Japan and identify them morphologically and molecularly using the 18S, D2-D3 regions of rRNA and mitochondrial cytochrome c oxidase subunit I (mtCOI). Hirschmanniella oryzae, commonly known to cause damage on rice in Japan, was also obtained and analysed for inter-and intraspecies sequence variations. All individuals of the genus Hirschmanniella extracted from lotus roots in 16 fields in ten prefectures were identified as H. diversa morphologically and molecularly. This result revealed that H. diversa is a dominant Hirschmanniella species parasitising lotus in Japan. Meanwhile, intraspecific sequence variations in H. diversa were relatively higher in the mtCOI (1-21 bases, <= 5.3%) than in the 18S rRNA and D2-D3 of 28S rRNA (0.0-0.3% and 0.0-0.4%, respectively) and in those of H. oryzae. Based on the mtCOI sequences, five haplotypes were identified and each haplotype was distributed in relatively close regions or regions in which the same lotus cultivars were grown, although further studies are required to verify this assertion. The morphological and genetic variations were higher in H. diversa than in H. oryzae (no intraspecific sequence variation in mtCOI), suggesting that H. diversa was not a recent invasive species.
  2023年10月, 研究論文（学術雑誌）, 共同, 25, 1, 1388-5545, DOI(公開)(r-map), 45, 58
• Effect of short-term growth of mung bean and its incorporation with nitrogen fertiliser on the density of the root-knot nematode, Meloidogyne incognita, in soil
  Zeng, Yayun; Perry, Roland N.; Toyota, Koki
  NEMATOLOGY
  BRILL
  Soybean is attacked by multiple plant-parasitic nematodes and the major ones are soybean cyst nematode (SCN) and root-knot nematodes. Our previous study reported that 2 weeks growth of mung bean and its soil incorporation markedly reduced SCN density in soil via hatching stimulation by mung bean residue. This study aimed: i) to evaluate whether incorporation of mung bean in combination with N fertiliser decreased the density of Meloidogyne incognita, which attacks both soybean and mung bean; and ii) to determine the direct effect of ammonium solutions on M. incognita J2 and hatching. The results showed that after the growth period of mung bean for 2 weeks and 4 weeks of its incorporation, the density of M. incognita was significantly reduced by 54 and 72% in the mung bean treatment with and without N fertiliser (140 mg N (kg soil)(-1)), respectively, compared with the control. Soil urease activity was significantly higher in the mung bean with N fertiliser than in the control. Meloidogyne incognita second-stage juveniles were less mobile in NH4Cl solutions with 100-250 mg N l(-1) than in 0 mg N l(-1). Moreover, NH4Cl solutions with 140 mg N l(-1) and 250 mg N l(-1) significantly inhibited the hatching of M. incognita. This study demonstrated that 2 weeks growth of mung bean may be a potential trap crop for M. incognita and N metabolism might be involved to a certain extent in the suppression of M. incognita.
  2023年09月, 研究論文（学術雑誌）, 共同, 25, 8, 1388-5545, DOI(公開)(r-map), 919, 928
• Positive priming effects through microbial P-mining in tropical forest soils under N2-fixing trees
  Sawada, Kozue; Kunito, Takashi; Watanabe, Tetsuhiro; Kitagawa, Natsuko; Lyu, Han; Nguyen, Ho Lam; Toyota, Koki; Funakawa, Shinya
  SOIL SCIENCE AND PLANT NUTRITION
  TAYLOR & FRANCIS LTD
  Phosphorus (P) addition is thought to have a minimal effect on the priming of preexisting soil organic carbon (C) mineralization after C addition. We hypothesized and tested that positive priming effects are driven by microbial P-mining under P-limitation when a relatively small amount of glucose is added to N-rich and P-poor tropical forest soils with N-2-fixing trees. The results showed that the addition of glucose alone (C) and the addition of C together with mineral N (CN) induced positive priming effects, while the addition of C together with mineral P (CP) and the addition of CNP did not, suggesting that positive priming effects occurred through microbial P-mining. The acid phosphatase activities were not much different in all treatments. The results support our hypothesis and suggest that positive priming effects will occur through microbial P-mining, independently of the hydrolysis of organic P esters with phosphatases, under P-limitation in N-rich and P-poor tropical forest soils.
  2023年07月04日, 研究論文（学術雑誌）, 共同, 69, 4, 0038-0768, DOI(公開)(r-map), 209, 214
• Effects of Rice Husk Biochar and Compost Amendments on Soil Phosphorus Fractions, Enzyme Activities and Rice Yields in Salt-Affected Acid Soils in the Mekong Delta, Viet Nam
  Linh, Doan Thi Truc; Khoi, Chau Minh; Ritz, Karl; Sinh, Nguyen Van; Phuong, Nguyen Thi Kim; My, Huynh Mach Tra; Linh, Tran Ba; Minh, Dang Duy; Linh, Thi Tu; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Given that rice husk biochar has been shown to modulate salinity in salt-affected acid soils, the objective of this study was to investigate the effects of organic amendment of salinized acid soils on P fractions, enzyme activities, and associated rice yield. Four treatments, viz. Rice-Rice-Rice, [RRR]; Fallow-Rice-Rice, [FRR]; Fallow-Rice-Rice + 3 Mg ha(-1) of compost [FRR + Comp]; and Fallow-Rice-Rice + 10 Mg ha(-1) of biochar [FRR + BC] were established at Ben Tre and Kien Giang sites, Viet Nam, over six consecutive crops. Soil properties at harvest of the sixth crop showed that there were diverse patterns of fractionation between P forms with respect to treatment. Overarchingly, biochar increased labile and moderately labile inorganic P and organic P by 30% to 70%, respectively, whilst compost had a relatively modest effect on these pools. Soil phosphatase activities at crop tillering increased following the FRR + Comp and FRR + BC treatments compared with those in RRR, except for acid phosphatase at Ben Tre. At harvest, there were no significant differences between the enzyme activities among the treatments. Rice yield was positively correlated with the more labile forms of P, soil C, and acid phosphatase activity. In the absence of organic amendments, there was no effect of triple versus double rice crops being grown in one-year cycle. Repeated application of biochar (10 Mg ha(-1) x 5 times) showed potential to increase grain yields and total soil C in salt-affected acid soils, via modulation of P transformations to more plant-available forms.
  2023年06月, 研究論文（学術雑誌）, 共同, 13, 6, DOI(公開)(r-map)
• Development of a simple test method for inhibitory effect of gall formation on Meloidogyne incognita and its application to nematicide screening
  Gunjima, Koshi; Toyota, Koki; Fujikawa, Aoto
  NEMATOLOGY
  BRILL
  For a screening test to discover nematicide candidates to control Meloidogyne incognita, a potted plant-based assay to observe gall formation on the root is realistic because it can cover the nematode life-cycle period and a broad range of mode of actions of tested compounds. However, both time and labour are needed for its operation. The objective of this study was to develop a plant-based screening method enabling easy periodical observation of the progress of root gall formation under almost no soil adsorption conditions of tested compounds. As an alternative material for soil, rockwool substrate for growing vegetable seedlings was used with a nutrient solution. Observation of gall formation on the same substrates was possible for 3-4 weeks. With this method, standard nematicides, e.g., fosthiazate and fluopyram, provided clear inhibitory effect on gall formation. Their ED50 values at 21 days after inoculation of 300 second-stage juveniles (substrate)-1 were 0.0034 mg (substrate)-1 and 0.0035 mg (substrate)-1, respectively. Furthermore, conventional fungicides and insecticides were screened with the method. Activities were observed in some products like polyoxins, which showed 100% control at 25 mg (substrate)-1, a considerably higher dose than that in standard nematicides. This study developed a simple test method for evaluating inhibitory effect on gall formation by M. incognita and proved its usefulness by applying it to nematicide screening.
  2023年02月, 研究論文（学術雑誌）, 共同, 25, 3, 1388-5545, DOI(公開)(r-map), 321, 333
• Transmissible Effects of a Biochar Amendment to an Upper Soil Zone Upon an Associated Lower Zone, Including Attenuation of Soybean Cyst Nematode (Heterodera glycines)
  Sinh, Nguyen Van; Linh, Doan Thi Truc; Phuong, Nguyen Thi Kim; Ritz, Karl; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Mung bean residues stimulate the hatching of soybean cyst nematode (SCN). In our previous study, combined incorporation of mung bean residues and biochar into soil can be effective in suppression of the soybean cyst nematode (SCN), Heterodera glycines, in the upper layer soil. However, there are no data available as to whether such effects are transmissible, and could for example be manifest in subsoil zones where such incorporation is confined to topsoils, via water-based pathways. We evaluated the effects of leachate passage from a biochar-amended soil in an upper soil zone to a lower zone in a microcosm-based system, upon a range of physicochemical properties and density of SCN. Disturbed soil was filled in a total of 9 cylindrical cores with two layers. The upper layer (0-15 cm) was amended with biochar at rates equivalent to 0, 0.3% or 1.8%, with bulk density set at of 1.1 g cm(-3). The lower layer (15-25 cm) without biochar amendment was compacted to 1.2 g cm(-3). Mung beans were grown for two weeks and incorporated into the upper layer. Water was surface-applied to the cores 4, 6, and 8 weeks after mung bean incorporation. After 16 weeks, the upper and lower layer soils were separately collected and assayed. The presence of biochar in the upper layer reduced the abundance of free-living nematodes, mainly bacterivorous, but increased that of a predator genus Ecumenicus in this zone. In the lower layer of soil under a biochar-amended upper layer, available P and soluble cations were increased as were abundances of total nematodes including Ecumenicus, resulting in greater maturity index, basal and structure indices. Notably, SCN density was decreased in lower zones by more than 90% compared to zero-biochar controls. This demonstrates that the effects of biochar upon soil properties, including impacts on biota and plant pathogens, are transmissible.
  2023年01月, 研究論文（学術雑誌）, 共同, 13, 1, DOI(公開)(r-map)
• Effects of Four Isothiocyanates in Dissolved and Gaseous States on the Growth and Aflatoxin Production of Aspergillus flavus In Vitro
  Hareyama, Yohei; Tarao, Mitsunori; Toyota, Koki; Furukawa, Tomohiro; Fujii, Yoshiharu; Kushiro, Masayo
  TOXINS
  MDPI
  Aflatoxins (AFs), a class of toxins produced by certain species of the genus Aspergillus, occasionally contaminate food and cause serious damage to human health and the economy. AFs contamination is a global problem, and there is a need to develop effective strategies to control aflatoxigenic fungi. In this study, we focused on isothiocyanates (ITCs) as potential chemical agents for the control of aflatoxigenic fungi. We quantitatively evaluated the effects of four ITCs (allyl ITC (AITC), benzyl ITC (BITC), and methyl and phenylethyl ITCs) in dissolved and gaseous states on the growth and aflatoxin B-1 production of Aspergillus flavus. In experiments using dissolved ITCs, BITC was found to be the strongest inhibitor of growth and aflatoxin B-1 production by A. flavus. Meanwhile, in the gaseous state, AITC strongly inhibited the A. flavus growth. When the concentration of ITCs in the liquid medium was quantified over time, AITC levels decreased to below the detection limit within 24 h, whereas BITC levels remained stable even after 48 h. These results suggested that when ITCs are utilized to control aflatoxigenic fungi, it is necessary to use them in a dissolved or gaseous state, depending on their volatility.
  2022年11月, 研究論文（学術雑誌）, 共同, 14, 11, DOI(公開)(r-map)
• A Biochar Improves the Efficacy of Green Manure-Based Strategies to Suppress Soybean Cyst Nematode (Heterodera glycines) and Promotes Free-Living Nematode Populations
  Sinh Van Nguyen; Chikamatsu, Seiya; Kato, Risako; Khoi Minh Chau; Phuong Kim Thi Nguyen; Ritz, Karl; Toyota, Koki
  JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION
  SPRINGER INT PUBL AG
  Purpose A method to control soybean cyst nematode (SCN) is to grow green manure which releases hatching stimulants in the absence of host plants. We hypothesized that biochar may improve the efficacy of this control strategy. Methods We evaluated the effects of two hatch-stimulating plants (Vigna radiata and Crotalaria spectabilis) in combination with rice husk biochar on the plant growth, SCN density, and soil nematode community. Plants were cultivated in biochar-amended and unamended soils for one month and then incorporated. Soils were collected periodically for chemical properties, SCN, and nematode community assessment. Results Biochar increased total biomass of V. radiata and C. spectabilis significantly. For V. radiata alone, the number of SCN juveniles (J2) increased at three weeks and then decreased, but in biochar-amended soil J2 prevailed for three to seven weeks after residue incorporation. In soil incorporated with C. spectabilis, J2 were sustained consistently in biochar-amended soil. Nine weeks after residue incorporation, real-time PCR assays revealed that V. radiata reduced the SCN density by 96% and 91%, and that C. spectabilis reduced the SCN density by 72% and 48% with and without biochar, respectively. Incorporation of green manure in biochar-amended soil increased microbial activity and abundance of omnivorous nematodes, notably Ecumenicus and Aporcelaimellus species which were negatively correlated with the SCN density. Specifically, V. radiata increased the composite and enrichment footprints of nematodes, and omnivore and structure footprints were further increased by combination with biochar. Conclusion Biochar may improve the efficacy of a green manure-based strategy to control SCN.
  2022年09月, 研究論文（学術雑誌）, 共同, 22, 3, 0718-9508, DOI(公開)(r-map), 3414, 3427
• Surface treatment of clayey soil particles for reducing water loss through evaporation
  Asanuma, Yosuke; Toyota, Koki; Nishimura, Taku; Lenggoro, I. Wuled
  ADVANCED POWDER TECHNOLOGY
  ELSEVIER
  To conserve water in crop production and landscaping, plastic mulch or sheets are commonly used. However, the environmental impact of plastic waste is a concern. Therefore, herein we report that a silane coupling agents-based coating can be applied to natural clayey soil samples to suppress water evaporation. The hydrophobicity of soils (particle sizes 200-500 p.m) can be enhanced. Evaporation flux was investigated using an electronic balance placed inside a chamber by maintaining constant flow, temperature, and relative humidity. The magnitude of evaporation flux was adjusted by placing a hydrophobic-treated soil layer in the system. It is clear that the hydrophobic-treated soil particle layer interacts with water capillaries to reduce the evaporation flux, but the effect on water vapor diffusion was small. (C) 2022 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
  2022年03月, 研究論文（学術雑誌）, 共同, 33, 3, 0921-8831, DOI(公開)(r-map)
• Influence of Rice Husk Biochar on Soil Nematode Community under Upland and Flooded Conditions: A Microcosm Experiment
  Van Sinh, Nguyen; Kato, Risako; Linh, Doan Thi Truc; Phuong, Nguyen Thi Kim; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Biochar has the potential for improving soil properties and supporting ecological functions, but it has negative impacts on soil organisms in some cases. This study aimed to assess the effect of biochar application at rates of 0 (B0), 5 Mg ha(-1) (B5), 20 Mg-1 (B20), and 40 Mg ha(-1) (B40) on soil nematode community under upland and flooded conditions in a short-term microcosm experiment. After biochar application, soil was incubated for 2 to 8 weeks and nematodes were identified for community composition, trophic structures, functional guilds, maturity index and metabolic footprints. The chemical properties of the soils were also analyzed. General linear model revealed that biochar increased soil pH, EC, NO3--N, available phosphorus, total C, and C/N ratio, particularly in the highest application rate and shifted the composition of nematodes. The greatest abundances of omnivores (Mesodorylaimus, Thornenema), predator (Nygolaimus) and functional guilds of cp5 were observed in B5, resulting in greatest structure footprint and composite footprint, (omnivorous + predator) footprint and total biomass in B5. While abundances of nematodes tended to decrease with the biochar applicate rates, the abundance of Prismatolaimus was the highest in B40. During the 8-week incubation period, the abundances of Achromadora, Alaimus, Aporcelaimellus, Cryptonchus, Mononchus, and Tobrilus remained stable in upland conditions. Under flooded conditions, the abundances of almost all taxa were markedly lower than those under upland conditions irrespective of biochar application, except for Acrobeloides, Alaimus, Aphelenchoides, and Ditylenchus. We highlighted that 5 Mg ha(-1) of rice husk biochar can be the optimum in shaping the nematode community.
  2022年02月, 研究論文（学術雑誌）, 共同, 12, 2, DOI(公開)(r-map)
• Impacts of conversion from natural forest to cedar plantation on the structure and diversity of root-associated and soil microbial communities
  Sawada, Kozue; Inagaki, Yoshiyuki; Sugihara, Soh; Funakawa, Shinya; Ritz, Karl; Toyota, Koki
  APPLIED SOIL ECOLOGY
  ELSEVIER
  Natural broadleaved forests have been widely converted to plantations with economically valuable trees mainly belonging to the family Pinaceae in temperate regions. Furthermore, mixed natural forests dominated by Pinaceae have been converted into pure cedar plantations involving members of the Cupressaceae in many areas. The objective of this study was to determine the impacts of such conversion with respect to the changes in dominant tree species and tree stand types (i.e. pure vs mixed) on soil properties, including the diversity and community structures of bacteria and fungi colonizing roots, rhizospheres, surface and subsurface bulk soils. Our results showed that vegetation apparently affected the bacterial and fungal community structures, but differently among these compartments. Bacterial alpha diversity was significantly lower in a mixed natural forest than in a pure cedar plantation. In addition, roots in the natural forest supported greater proportions of specific bacteria such as Bradyrhizobiaceae and Burkholderia bryophila, which have been often reported as plant-growth-promoting rhizobacteria. Fungal alpha diversity was not different between vegetation, but ectomycorrhizal (ECM) fungi such as Piloderma olivaceum, Cenococcum geophilum, Tuber pseudosphaerosporum, Sebacina sp. Tomentella sp. and Russula sp. were detected in the natural forest but less than 0.2% in the cedar plantation. The rhizosphere effects on soil pH and bacterial and fungal abundance were observed only in the natural forest, but not in the cedar plantation. Therefore, our results suggested that conversion from mixed natural forest to pure cedar plantation reduces specific bacteria with plant-growth-promoting properties as well as ECM fungi, although it appears to increase bacterial diversity. This has practical implications in that it suggests that specific planting of ECM-associated trees might be an effective strategy when attempting to generate mixed forests from starting points of pure cedar plantations.
  2021年11月, 研究論文（学術雑誌）, 共同, 167, 0929-1393, DOI(公開)(r-map), 104027
• Development and application of a DNA metabarcoding method for comprehensive analysis of soil nematode communities
  Kawanobe, Masanori; Toyota, Koki; Ritz, Karl
  APPLIED SOIL ECOLOGY
  ELSEVIER
  Nematodes mediate soil ecosystem functions together with other soil biota and are employed as effective ecological indicators. Among nematodes, plant-parasitic nematodes are economically important due to the damage they cause to many crops. While morphological identification of nematodes after elutriation from soil has been widely used to assess their diversity and for diagnostic analyses, high-throughput sequencing techniques are becoming more widely available. In this study, highly sensitive primer sets using the 18S rDNA region as metabarcoding markers were developed specifically for soil nematode fauna using next generation sequencing (NGS). In silico analysis using Primer BLAST identified a primer set (F548_A/R1912) specific to nematodes and is effective in application to DNA directly extracted from soil as well as from elutriated nematode populations. In silico analysis also indicated that three primer sets (F548_A/R915, F548_A/SSU26R and F548_A/R1912) developed in this study were expected to properly amplify the target sequences of 97-98% of 88 selected free-living and 83-92% of 60 selected plant-parasitic nematode species. All the results of NGS using three primer sets applied to DNA from a nematode suspension and the nematode specific primer set applied to soil DNA showed significant (p < 0.01, linear mixed-effects model) correlations with the results of nematode enumeration using a morphological approach. Furthermore, all the NGS assays indicated population structures were 3-9% more diverse than the microscopic approach. The current NGS protocol detects a proper level of sequence reads to represent nematode fauna for diversity and diagnostic analyses in 5 soil sampling sites in Japan, based on the rarefaction curves. As a result, this study revealed that the primer set F548_A/R1912 is highly specific to nematode species and applicable to soil DNA, and further F548_A/R915 and F548_A/SSU26R may extend the coverage to detect more nematode species than that using only F548_A/R1912 with soil DNA. The three primer sets and the metabarcoding protocol examined appear suitable for comprehensive studies of nematode community structure.
  2021年10月, 研究論文（学術雑誌）, 共同, 166, 0929-1393, DOI(公開)(r-map), 103974
• Comparison of the Structure and Diversity of Root-Associated and Soil Microbial Communities Between Acacia Plantations and Native Tropical Mountain Forests
  Sawada, Kozue; Watanabe, Shinichi; Nguyen, Ho Lam; Sugihara, Soh; Seki, Mayuko; Kobayashi, Hana; Toyota, Koki; Funakawa, Shinya
  FRONTIERS IN MICROBIOLOGY
  FRONTIERS MEDIA SA
  Deforestation of native tropical forests has occurred extensively over several decades. The plantation of fast-growing trees, such as Acacia spp., is expanding rapidly in tropical regions, which can contribute to conserve the remaining native tropical forests. To better understand belowground biogeochemical cycles and the sustainable productivity of acacia plantations, we assessed the effects of vegetation (acacia plantations vs. native forests) and soil types (Oxisols vs. Ultisols) on soil properties, including the diversity and community structures of bacteria- and fungi-colonizing surface and subsurface roots and soil in the Central Highlands of Vietnam. The results in surface soil showed that pH was significantly higher in acacia than in native for Oxisols but not for Ultisols, while exchangeable Al was significantly lower in acacia than in native for Ultisols but not for Oxisols. Bacterial alpha diversity (especially within phylum Chloroflexi) was higher in acacia than in native only for Oxisols but not for Ultisols, which was the same statistical result as soil pH but not exchangeable Al. These results suggest that soil pH, but not exchangeable Al, can be the critical factor to determine bacterial diversity. Acacia tree roots supported greater proportions of copiotrophic bacteria, which may support lower contents of soil inorganic N, compared with native tree roots for both Oxisols and Ultisols. Acacia tree roots also supported greater proportions of plant pathogenic Mycoleptodiscus sp. but appeared to reduce the abundances and diversity of beneficial ECM fungi compared with native tree roots regardless of soil types. Such changes in fungal community structures may threaten the sustainable productivity of acacia plantations in the future.
  2021年09月29日, 研究論文（学術雑誌）, 共同, 12, DOI(公開)(r-map)
• Priming effects induced by C and N additions in relation to microbial biomass turnover in Japanese forest soils
  Sawada, Kozue; Inagaki, Yoshiyuki; Toyota, Koki
  APPLIED SOIL ECOLOGY
  ELSEVIER
  An understanding of the priming effect (PE), i.e. the effects of carbon (C) and nitrogen (N) inputs on the priming of pre-existing soil organic C mineralization, is fundamental to predicting future soil C cycling and climate feedback. Since the direction and magnitude of the PE depend on the turnover of microbial biomass C and N, we evaluated the PE in relation to pre-existing biomass C and N using dual labeling of glucose C-13 and mineral N-15 for Japanese moderately acidic (pH of 5.0) cedar and strongly acidic (pH of 4.1) cypress soils. The addition of C only to the cedar soil caused no PE with no change in biomass turnover relative to the control without C or N additions. The addition of N with C caused a positive PE, leading to a net loss of soil C stocks, and decreased pre-existing biomass N due to the higher turnover of biomass N relative to the control. The result for the cedar soil was in line with the stoichiometric decomposition theory but not with microbial N mining theory. By contrast, the addition of C only and both C and N to the cypress soil caused a negative PE. Our study revealed that increasing the pre-existing biomass N turnover can lead to a positive PE, accelerating net soil C loss, when the soil pH does not limit microbial activities.
  2021年06月, 研究論文（学術雑誌）, 共同, 162, 0929-1393, DOI(公開)(r-map)
• An Empirical Method for Diagnosing Premature Bolting Risk in Spring Cabbage by Estimating the Flower Bud Differentiation Period
  Takada, Atsushi; Okada, Kunihiko; Toyota, Koki
  HORTICULTURE JOURNAL
  JAPAN SOC HORTICULTURAL SCI
  Spring cabbage (Brassica oleracea var. capitata L.) is a crop type in which sowing is performed in fall and harvesting in spring. The flower bud differentiation, explained as the phase transition from the vegetative phase to reproductive phase, is induced by chilling after a certain plant size, then the risk of premature bolting is triggered by long days and high temperatures. Farmers empirically avoid bolting by selecting suitable varieties and sowing days. However, climate change may increase the risk of premature bolting. The objectives of this study were to evaluate the relationship between the number of head leaves at flower bud differentiation and premature bolting, and to develop a model to predict flower bud differentiation and the number of head leaves using data on the daily cumulative temperature. Firstly, we found that the risk of premature bolting was high for the 'Kinkel-201' cabbage variety when the number of head leaves (> 1 g) was less than 6.5 leaves in the flower bud differentiation period. The number of head leaves (> 1 g) (y) was estimated by the daily cumulative temperature (x): y = 0.0248x - 24.485 to 28.613, depending on year. The flower bud differentiation period was estimated based on the concept of the developmental rate (DVR) and the developmental index (DVI), in which the value of DVI at sowing was defined as 0 and that at the flower bud differentiation period as 1. Each parameter's response to the cold treatment stage (RS) and the response to chilling (C) was estimated based on the daily mean temperature. The DVR model predicted the flower bud differentiation period in 2010-2014 with a root mean squared error = 5.3 days (without outliers). Therefore, the risk of premature bolting is predictable by estimating the number of head leaves (> 1 g) at the flower differentiation period using data on sowing date and mean temperature.
  2021年04月, 研究論文（学術雑誌）, 共同, 90, 2, 2189-0102, DOI(公開)(r-map), 190, 201
• Impacts of saltwater intrusion on soil nematodes community in alluvial and acid sulfate soils in paddy rice fields in the Vietnamese Mekong Delta
  Sinh Nguyen, Van; Chau, Minh Khoi; Vo, Quang Minh; Le, Van Khoa; Nguyen, Thi Kim Phuong; Araki, Masaaki; Perry, Roland N.; Tran, Anh Duc; Dang, Duy Minh; Tran, Ba Linh; Chol, Gyu Lee; Toyota, Koki
  ECOLOGICAL INDICATORS
  ELSEVIER
  Saltwater intrusion is a potential risk damaging crop diversity and productivity due to degraded soil physicochemical properties. However, little is known about how salinity affects the structure and function of soil nematodes community in intensive rice cultivated area. This study aimed (1) to assess the impacts of saltwater intrusion on the nematode community in alluvial and acid sulfate soils; and (2) to evaluate its relation with soil conditions. Saltwater intrusion reduced the abundance of both free-living nematodes (FLN) and plant-parasitic nematodes (dominated by Hirschmanniella) in soils. FLN community was different among sites with different physicochemical properties. The omnivorous genera Aporcelaimellus and Thornenema were only found in nonsalt-affected alluvial soil, whilst Mesodorylaimus was dominant in salt-affected acid sulfate soil, suggesting that this genus might be tolerant to higher EC and soluble Na+, K+, Ca2+. The bacterivorous nematodes (dominant taxa Chronogaster, Rhabdolaimus) were dominant in both non-salt affected and salt-affected alluvial soils, which accounted for 48% and 40%, respectively, whilst it accounted for 21% in salt-affected acid sulfate soil. The abundance of fungivorous nematodes (Aphelenchoides, Ditylenchus, Filenchus) were greater in salt-affected alluvial soil in contrast to the other treatments, suggesting that these might be tolerant to salinity and low pH. Saltwater intrusion reduced biological diversity (Margalef, Shannon-Wiener, and Hill's indices), maturity index (Sigma MI, MI25), and clearly affected functional guilds of nematode community, especially c-p 5 group was reduced in both salt-affected soils. This study suggests that saltwater intrusion showed a potential risk in the degradation of soil properties, as indicated by the altered nematode community, trophic structure, functional guilds and their ecological indices in paddy fields.
  2021年03月, 研究論文（学術雑誌）, 共同, 122, 1470-160X, DOI(公開)(r-map), 107284
• Suppression of the soybean cyst nematode, Heterodera glycines, by short-term field cultivation and soil incorporation of mung bean
  Chikamatsu, Seiya; Takeda, Ai; Ohta, Kazuhiro; Imura, Takeo; Perry, Roland N.; Toyota, Koki
  NEMATOLOGY
  BRILL
  Our previous study using pots reported that short-term growth of mung bean (Vigna radiata) may be useful to decrease the density of the soybean cyst nematode (SCN), Heterodera glycines, in soil. The objective of this study was to determine whether short-term growth of mung bean and its incorporation by ploughing decreased SCN density in infested fields. Firstly, we did pot experiments to evaluate the optimum temperature and moisture for hatching in soil. SCN hatching was stimulated at 25 and 30 degrees C and not at 20 degrees C; however, it was stimulated at alternating temperature conditions between 20 and 25 degrees C. Soil moisture levels with pF 2.76 or less were required to stimulate SCN hatch in soil. Field experiments were done in Saitama, Kanagawa and Nara Prefectures, Japan. SCN density was reduced by nearly half even in control plots, in which mung bean was not cultivated and ploughed. in Saitama and Nara Prefectures. However, SCN density was reduced by nearly 80% or more in the three Prefectures, except for one plot in Kanagawa, and the soil temperature and moisture conditions were kept at around 20-30 degrees C and at < pF 2.8. Increase in yield of green soybean by SCN control was estimated at 350 kg (1000 m)(-2). Overall, the present study revealed that short-term field cultivation of mung bean and ploughing was a profitable method to decrease SCN density in infested fields and thereby to increase yield of green soybean.
  2021年03月, 研究論文（学術雑誌）, 共同, 23, 3, 1388-5545, DOI(公開)(r-map), 305, 315
• Impacts of Fallow Conditions, Compost and Silicate Fertilizer on Soil Nematode Community in Salt-Affected Paddy Rice Fields in Acid Sulfate and Alluvial Soils in the Mekong Delta, Vietnam
  Van Sinh, Nguyen; Khoi, Chau Minh; Phuong, Nguyen Thi Kim; Linh, Tran Ba; Minh, Dang Duy; Perry, Roland N.; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Avoidance of intensive rice cultivation (IRC) and soil amendments are potential practices to enhance soil properties. There is only limited information on the effects of reduced IRC and its mixture with compost or silicate fertilizer (Si) on the soil nematode community in salt-affected soils. This study aimed to assess the shifts of soil nematode community by reducing a rice crop from triple rice system (RRR) to a double rice system and mixed with compost or Si in paddy fields in acid sulfate soil (ASS) and alluvial soil (AL) in the Mekong Delta, Vietnam. Field experiments were designed with four treatments in four replicates, including RRR and a proposed system of double-rice followed by a fallow (FRR) and with 3 Mg ha(-1) crop(-1) compost or 100 kg ha(-1) crop(-1) Si. Soils were collected at harvest after the 2 year experiment, reflecting the fifth and third consecutive rice crop in RRR and FRR system, respectively. Results showed that reduced IRC gave a significant reduction in abundance of plant-parasitic nematodes (PPN), dominated by Hirschmanniella and increased abundance bacterivorous nematodes when mixed to compost and silicate fertilizer in ASS. In addition, reduced IRC increased nematode biodiversity Hill's indices and reduced herbivorous footprint in ASS. Proposed system having compost or Si had strongly increased in bacterivorous and omnivorous footprints. Particularly, reduced IRC mixture with Si increased abundance of Rhabdolaimus, Mesodorylaimus and Aquatides, metabolic footprints (structure footprint, bacterivorous, omnivorous and predator) and diversity Hill's N1 index in ASS. Our results highlighted that reduced IRC was a beneficial practice for decreasing abundance of PPN in salt-affected soils and increasing abundance of FLN in ASS. IRC mixture with compost or Si had potential in structuring the nematode communities with increasing biodiversity, trophic structure, and metabolic footprints.
  2021年03月, 研究論文（学術雑誌）, 共同, 11, 3, DOI(公開)(r-map), 425
• Seasonal variation and vertical distribution of nematode communities and their relation to soil chemical property and rice productivity under triple rice cultivation in the Mekong Delta, Vietnam
  Sinh Van Nguyen; Phuong Kim Thi Nguyen; Araki, Masaaki; Perry, Roland N.; Linh Ba Tran; Chau, Khoi Minh; Min, Yu Yu; Toyota, Koki
  NEMATOLOGY
  BRILL
  Rice is an important agricultural crop in Vietnam. Nematodes are diverse in soil agroecosystems. However, little is known about their seasonal variation in extremely intensive rice cultivation in tropical regions. The objectives of this study were to investigate the seasonal variation and spatial distribution of the nematode community, and to assess its relationship with the soil chemical property and lice yield. Soils (0-10 cm and 10-20 cm deep) were collected at harvest in spring-summer (S-S). summer-autumn (S-A), and winter-spring (W-S) cultivation in 2017 and 2018. Plant-parasitic nematodes were the largest group and accounted for 47-80 and 79-92% of total nematode abundance in the topsoil and subsoil, respectively. Hirschmanniella was the most dominant taxon whose abundance in topsoil varied from 275-739 in W-S to 1010-1270 indiv. (1(X) g soil)(-1) in the S-S season. Nematode assemblages differed between topsoil and subsoil, and those of topsoil had clear seasonal distribution patterns. Bacterivore nematodes were the predominant group of free-living nematodes, with increasing relative abundance in the topsoil of S-S (average 23.2% of total free-living nematodes) < S-A (average 41.9%) < W-S (average 57.3%). Furthermore, soil in the W-S season had the highest microbial activity in 2018. Soil pH, EC and abundance of Hirschmanniella spp. were significantly negatively related with rice yield. The present results suggest that the presence of Hirschmanniella spp. in soil may be involved in a reduction of rice yield in the triple rice system.
  2021年02月, 研究論文（学術雑誌）, 共同, 23, 1, 1388-5545, DOI(公開)(r-map), 33, 46
• Studies on ecology, diagnosis, and control of soilborne plant pathogens and plant parasitic nematodes: a synthesis
  Toyota, Koki
  SOIL SCIENCE AND PLANT NUTRITION
  TAYLOR & FRANCIS LTD
  Continuous cropping often leads yield losses via deteriorated soil biological and chemical properties. In this mini review, the importance of organic matter amendment is focused in relation to the management of soilborne plant pathogens and plant parasitic nematodes. A wide range of examples are shown for organic matter amendment including composts, cover crops and simple organic compound to suppress the densities of pathogens and nematodes. A novel diagnostic method using real-time PCR is also shown for plant parasitic nematodes.
  2021年01月02日, 研究論文（学術雑誌）, 単独, 67, 1, 0038-0768, DOI(公開)(r-map), 18, 25
• Infestation of rice white tip nematode, Aphelenchoides besseyi (Christie, 1942), in Myanmar
  Lin Zar Ni, Yu Yu Min and Koki Toyota
  Russian Journal of Nemaology
  2020年12月, 研究論文（学術雑誌）, 共同, 28, DOI(公開)(r-map), 85, 89
• Effects of cropping systems and soil amendments on nematode community and its relationship with soil physicochemical properties in a paddy rice field in the Vietnamese Mekong Delta
  Sinh Van Nguyen; Phuong Thi Kim Nguyen; Araki, Masaaki; Perry, Roland N.; Linh Ba Tran; Khoi Minh Chau; Min, Yu Yu; Toyota, Koki
  APPLIED SOIL ECOLOGY
  ELSEVIER
  Long-term intensive rice monoculture, triple rice cultivation (rice crops are cultivated three times per year) in the Mekong Delta, Vietnam, causes a reduction in topsoil quality. Rotating rice with an upland crop in a tropical paddy field may improve the soil physicochemical properties but effects on the soil nematode community are unknown. This study was conducted in a triple rice field to evaluate the responses of the nematode community to a crop rotation (the first rice in a year was replaced with sesame and soybean, and the second and third crops were rice) and to organic amendment. The experiment was based on a split-plot design with two factors that were crops (main factor, n = 3) and compost amendment (sub-factor, n = 3). The crops were rice, soybean, and sesame and the sub-factors were cow manure plus rice straw compost, sugarcane compost, and no amendment. Soil samples were taken at harvest of the first crops in topsoil (0-10 cm) and subsoil (10-20 cm) in 2017 and 2018. In 2018, the abundance of free-living nematodes (FLN), which were dominated by bacterivores and fungivores, was greater in upland crops, while that of plant-parasitic nematodes (PPN) was greater in paddy rice. In particular, the density of the most predominant PPN genus, Hirschmanniella, was lower in upland crops than in paddy rice. Cultivation of sesame also reduced the number of the second predominant PPN genus, Bitylenchus, resulted in an increase in the ratio of the free-living to plant-parasitic nematodes. The diversity evenness index (J), Shannon-Wiener (H') and Hill's indices increased in upland crops compared to those in rice fields in 2018. Crop rotation with sesame or soybean in a paddy field enhanced abundance and biodiversity of FLN and suppressed PPN and thus can be proposed for agricultural sustainability.
  2020年12月, 研究論文（学術雑誌）, 共同, 156, 0929-1393, DOI(公開)(r-map)
• Distribution of Pigeon Pea Cyst Nematode and Root-Knot Nematodes in Major Sesame Growing Areas in Myanmar
  Min, Yu Yu; Naing, Thu Htet; Htun, Nwe Nwe; Myint, Aung Kyaw; Ichinose, Yuri; Perry, Roland N.; Yoshimura, Atsushi; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  The pigeon pea cyst nematode, Heterodera cajani, is an economically important plant-parasitic nematode in sesame production. The objective of the study was to investigate distribution of H. cajani in the major sesame producing areas in Myanmar. Before cultivation, soil samples were collected in 96 local farmer's fields: (19 fields in Magway, 20 fields in Mandalay, 14 fields in Sagaing and 43 in Nay Pyi Taw), and nematode density was quantified by real-time PCR. The cyst nematode was detected in 63.2% of the fields in Magway and the mean density was 22.6 eggs equivalent (20 g soil)(-1). In Mandalay and Nay Pyi Taw, the cyst nematode was detected in 40.0% and 18.6% of the fields with the mean densities of 9.9 and 21.0 eggs equivalent (20 g soil)(-1), respectively. By contrast, the cyst nematode was not detected in Sagaing fields, in which sesame is rotated with paddy rice. Infestation of root-knot nematodes (RKN, Meloidogyne spp.) was also evaluated, because sesame is generally rotated with rice and pulses, which are attacked by RKN. The results showed 25.6% infestation of RKN with a mean density of 34.3 eggs equivalent (20 g soil)(-1) only in Nay Pyi Taw, while there was no infestation in Magway, Mandalay, and Sagaing. The relationships between the nematode infestation level and the cropping patterns in each sesame growing area in Myanmar were discussed.
  2020年10月, 研究論文（学術雑誌）, 共同, 10, 10, DOI(公開)(r-map)
• Influence of Rice Husk Biochar and Compost Amendments on Salt Contents and Hydraulic Properties of Soil and Rice Yield in Salt-Affected Fields
  Nguyen Thi Kim Phuong; Chau Minh Khoi; Ritz, Karl; Tran Ba Linh; Dang Duy Minh; Tran Anh Duc; Nguyen Van Sinh; Thi Tu Linh; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Soil salinity may damage crop production. Besides proper management of irrigation water, salinity reduction can be achieved through soil amendment. The objectives of this study were to evaluate the effects of rice husk biochar and compost amendments on alleviation of salinity and rice growth. Field experiments were conducted at two salt-affected paddy rice fields located in distinct sites for five continuous crops. Treatments, with four replicates, consisted of continuous three rice crops per year (RRR), two rice crops rotated with fallow in spring-summer crop (FRR), FRR plus compost at 3 Mg ha(-1)crop(-1)(FRR + Comp), and biochar at 10 Mg ha(-1)crop(-1)(FRR + BC). Salt contents and hydraulic properties of soils, plant biomass, and plant uptake of cations were investigated. Soil bulk density (BD), exchangeable sodium (Na+), and exchangeable sodium percentage (ESP) were reduced remarkably by biochar application. Biochar application significantly increased other soil properties including total porosity, saturated hydraulic conductivity (Ksat), soluble and exchangeable potassium (K+), K+/Na(+)ratio, available P, and total C. Compost application also improved BD, total porosity, and available P, but not exchangeable Na(+)and ESP. Total aboveground biomass of rice showed a trend of FRR + BC > FRR + Comp > FRR > RRR. Relatively higher K(+)uptake and lower Na(+)uptake in rice straw in FRR + BC resulted in a significant two times higher K+/Na(+)ratio over other treatments. Our results highlight that biochar amendment is a beneficial option for reducing ESP and providing available K(+)and P under salinity-affected P-deficient conditions, hence improving straw biomass.
  2020年08月, 研究論文（学術雑誌）, 共同, 10, 8, DOI(公開)(r-map)
• Distribution of Root-Lesion and Stunt Nematodes, and Their Relationship with Soil Properties and Nematode Fauna in Sugarcane Fields in Okinawa, Japan
  Kawanobe, Masanori; Sugihara, Soh; Miyamaru, Naoko; Yoshida, Koichi; Nonomura, Eito; Oshiro, Hiroaki; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Sugarcane cultivation in Japan has not yet focused on suppressing plant-parasitic nematodes. For proper nematode management, it is essential to know the spatial distribution of economically important plant-parasitic nematodes and free-living nematodes that play important roles in terrestrial ecosystems. We aimed to reveal nematode fauna and soil properties in 85 sugarcane fields of three major sugarcane producing islands in Japan, and to examine their relationship by using the mixed-effect model and by visualizing the spatial distributions using the inverse distance weighting (IDW) approach. The nematode community structures were analyzed by non-metric multidimensional scaling (NMDS). Among plant-parasitic nematodes in sugarcane, the root-lesion nematodes (Pratylenchussp.) and the stunt nematodes (Tylenchorhynchussp.) were widely distributed in these islands, yet the abundance and the species varied geospatially. Soil pH was significantly correlated with the abundance ofPratylenchusandTylenchorhynchusspecies. The abundance ofPratylenchusandTylenchorhynchusspecies were significantly correlated with soil pH. The abundance ofPratylenchuswas significantly correlated with the abundance of free-living nematodes, the number of free-living nematode species, and exchangeable cation K+, as were the abundance ofTylenchorhynchusto the clay content and that of non-Tylenchorhynchus. This study also revealed that the three islands had different nematode faunas, which were explained especially by soil pH, texture, and exchangeable basic cations.
  2020年06月, 研究論文（学術雑誌）, 共同, 10, 6, DOI(公開)(r-map)
• Potential Use of Rice Husk Biochar and Compost to Improve P Availability and Reduce GHG Emissions in Acid Sulfate Soil
  Nguyen Thi Kim Phuong; Khoi, Chau Minh; Ritz, Karl; Nguyen Van Sinh; Tarao, Mitsunori; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  Acid sulfate soil (ASS) has major problems related to phosphorus deficiency and high potential for N2O emissions, as well as strong acidity. The objective of this study was to evaluate the effects of rice husk biochar and compost on P availability and greenhouse gas (GHG) emissions in ASS in in vitro incubation studies. An ASS was amended with two types of rice husk biochar (at rates of 0 g kg(-1), 20 g kg(-1), and 50 g kg(-1), equivalent to 0 Mg ha(-1), 20 Mg ha(-1), and 50 Mg ha(-1), assuming that bulk density was 1 g cm(-3) and evenly applied for 10 cm in depth) and compost (at rates of 0 g kg(-1), 10 g kg(-1), and 20 g kg(-1), equivalent to 0 Mg ha(-1), 10 Mg ha(-1), and 20 Mg ha(-1)) and incubated. Application of compost increased labile P by 100% and 200% at rates of 10 g kg(-1) and 20 g kg(-1), respectively. Both biochars showed an increase in NaHCO3-soluble inorganic P by 16% to 30%, decreases in NaOH-soluble inorganic P and NaHCO3-soluble organic P. N2O emissions were significantly decreased by 80% by a biochar with a higher surface area and higher NH4+ adsorption capacity at a rate of 50 g kg(-1) as compared with those in un-amended soil. In contrast, compost amendment at a rate of 10 g kg(-1) significantly increased N2O emission by 150%. These results suggest that in ASS, whilst compost is more effective in improving P availability, biochar is more effective in mitigating GHG emissions, emphasizing that fundamental characteristics of organic amendments influenced the outcomes in terms of desirable effects.
  2020年05月, 研究論文（学術雑誌）, 共同, 10, 5, DOI(公開)(r-map)
• Screening of Nematicides against the Lotus Root Nematode, Hirschmanniella diversa Sher (Tylenchida: Pratylenchidae) and the Efficacy of a Selected Nematicide under Lotus Micro-Field Conditions
  Takagi, Motonori; Goto, Maki; Wari, David; Saito, Mina; Perry, Roland N.; Toyota, Koki
  AGRONOMY-BASEL
  MDPI
  In Japan, Hirschmanniella diversa is an important pest in lotus cultivation in paddy fields and only lime nitrogen is registered for its control. Therefore, additional nematicides are required to control the nematode. The objective of this study was to screen for an effective nematicide. Fourth-stage juveniles and adults of H. diversa sampled from a lotus field were tested in in vitro solution experiments against 37 pesticides that are registered for the pest control of crops in Japan. Carbamate-based benfuracarb, organophosphate-based fenthion, nereistoxin-based cartap hydrochloride and cyanamide showed nematicidal effects against H. diversa. Benfuracarb at 1 mu g/mL showed a nematostatic effect on H. diversa in an agar plate assay. Further, H. diversa treated with benfuracarb did not resume activity 7 days post nematicide treatment when transferred to distilled water. Benfuracarb was tested in micro-field experiments, in which H. diversa density and lotus tuber damage levels were monitored. Results showed that benfuracarb reduced H. diversa densities in the roots during the cultivation period in 2012 and consistently reduced damage levels during a five year study period. Thus, benfuracarb is recommended as an effective nematicide to be used for H. diversa control in lotus cultivation.
  2020年03月, 研究論文（学術雑誌）, 共同, 10, 3, DOI(公開)(r-map)
• Decreases in inorganic nitrogen inputs and effects on nitrogen saturation and soil acidification
  Baba, Mitsuhisa; Okazaki, Masanori; Matsuda, Kazuhide; Shima, Emu; Tachiyanagi, Fuka; Sugiura, Toshihiro; Toyota, Koki
  JOURNAL OF FOREST RESEARCH
  TAYLOR & FRANCIS LTD
  We aimed to elucidate the effects of decreases in nitrogen (N) inputs on N budgets and soil acidity in N saturated forests in Tokyo, Japan using new analysis and comparison to sampling data collected in the 1990s. Canopy throughfall and soil-percolated water samples were collected from stands of Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa), where allophanic Andisols have developed. Stream water was sampled at the outlet of the catchment (2.15 ha). The total inorganic N input due to throughfall in the Japanese cypress stand was 104-184 mmolc m(-2) year(-1), which is a marked decrease from sampling results from the 1990s (1991-1992 and 1995). This decrease can be ascribed to a reduction in NOx emission from automobiles. Consequently, nitrate (NO3-) outputs from the catchment decreased when compared with the previous study, although outputs were comparable to N inputs. Based on i) N budgets for the catchment and ii) episodic acidification of stream water, the study site remains N saturated. The degree of decrease in ammonium (NH4+) inputs was larger than NO3- inputs, which resulted in a decrease in acid production due to nitrification or plant uptake and contributed to reduced soil acidification. As a result, the pH values of soil-percolated water in the Japanese cypress stand increased slightly, compared to levels in the 1990s. On the other hand, soil pH values in the Japanese cypress stand were comparable to those in the 1990s due to the large acid-neutralizing capacity of allophanic Andisols.
  2020年01月02日, 研究論文（学術雑誌）, 共同, 25, 1, 1341-6979, DOI(公開)(r-map), 31, 40
• Monthly and Yearly Variations in Oxygen Radical-scavenging Activity, Ascorbic Acid Content, and Degrees Brix of Komatsuna (Brassica rapa var. perviridis) in the Kanto Region, Japan
  Takei, Ayuchi; Goh, Yuri; Hattori, Gen; Arii, Masayuki; Niwa, Masumi; Toyota, Koki
  HORTICULTURE JOURNAL
  JAPAN SOC HORTICULTURAL SCI
  It is commonly recognized that vegetables in their best season are delicious and have high nutritional value. We investigated the monthly and yearly variations in radical-scavenging (RS) activity, an indicator of antioxidant activity, ascorbic acid, and degrees Brix of Brassica rapa var. perviridis (komatsuna) cultivated in the Kanto region, Japan. RS activity was significantly higher in December, January, and February than in the other months in all tested years (2010-2015). For two varieties (summer and winter varieties) their RS activity was significantly higher in winter than in summer. The weight proportion of leaf blades and petioles at harvest was similar (leaf blade:petiole = 4:6) both in the summer and winter, indicating that the difference in the RS activity of komatsuna between the two seasons was not due to the weight ratio, but to the increase in the RS activity of leaf blades in the winter. There were no significant differences in the RS activity of komatsuna between summer (30 days) and winter (80 days) cultivation periods, greenhouse and open-field cultivations, and producers. Multiple years of field studies revealed that the antioxidant activity, ascorbic acid content, and degrees Brix of komatsuna in the Kanto region were higher in winter than in other seasons, and suggested that komatsuna with a similar quality level may be produced when grown in regions with similar weather conditions.
  2020年, 研究論文（学術雑誌）, 共同, 89, 3, 2189-0102, DOI(公開)(r-map), 251, 260
• Evaluation of Nematicidal Activity of Fluensulfone against Non-Target Free-Living Nematodes under Field Conditions
  Kawanobe, Masanori; Toyota, Koki; Fujita, Tomonori; Hatta, Daisuke
  AGRONOMY-BASEL
  MDPI
  The use of nematicides with reduced toxic side-effects against non-target free-living nematodes is a favorable option for farmers to control plant-parasitic nematodes. The nematicide fluensulfone was registered in several countries for the control of the root-knot nematodes, Meloidogyne spp. among other plant-parasitic nematodes. This study aimed to evaluate the nematicidal activity of fluensulfone against non-target nematode fauna in four field experiments, each under different conditions (soils types and plant hosts). Nematodes extracted from soil samples were classified and counted based on their morphological characters. Fluensulfone significantly reduced damage caused by root-knot nematodes to tomato and sweet potato plants, while overall non-target free-living nematode population densities were maintained at the same level as those in control. Different diversity indices (e.g., Shannon-Wiener H', Simpson's D, species richness, evenness J', maturity indices) and principal component analyses in the four experiments showed that fluensulfone treatment kept a similar diversity level of non-target free-living nematode fauna to that of the non-treated control. The results suggested that fluensulfone may have minimal impact to free-living nematode fauna in both population density and diversity when the nematicide was applied to control Meloidogyne spp.
  2019年12月, 研究論文（学術雑誌）, 共同, 9, 12, DOI(公開)(r-map), 853
• Masanori Kawanobe, Naoko Miyamaru, Koichi Yoshida, Takeshi Kawanaka,Tomonori Fujita and Koki Toyota
  Sugarcane yield loss in the ratoon crop carried over from the plant crop damaged by plant-parasitic nematode in a heavy clay field in Okinawa, Japan
  Nematological Research
  2019年12月, 研究論文（学術雑誌）, 共同, 49, 1, 1, 6
• Seasonal occurrence and life cycle of lotus root nematode Hirschmanniella diversa (Tylenchida: Pratylenchidae) in lotus roots in paddy fields
  Takagi, Motonori; Goto, Maki; Wari, David; Kashima, Tetsuro; Toyota, Koki
  APPLIED ENTOMOLOGY AND ZOOLOGY
  SPRINGER JAPAN KK
  The lotus root nematode, Hirschmanniella diversa Sher (Tylenchida: Pratylenchidae), causes damage to lotus tubers, and thus decreases its economic value. Few studies have elucidated the life cycle of H. diversa, which is essential to optimize control methods. Therefore, we collected H. diversa from lotus roots and investigated its seasonal population fluctuations, female mating rates, stylet, and body lengths to understand its seasonal occurrence and possibly predict its life cycle. Hirschmanniella diversa were sampled from two lotus paddy fields between 2010 and 2012 in Ibaraki Prefecture, Japan. The occurrence of H. diversa increased with time peaking around late August and early September, then depreciating thereafter. The seasonal breeding period determined by quantifying the number of H. diversa females with spermatheca filled with sperm peaked from April until mid-May and decreased subsequently. Furthermore, overwintered adult H. diversa females laid eggs around June, hence possibly mating between April and May. Second-stage juveniles emerged at the beginning of August and continued developing thereafter. The fourth-stage juveniles or adults overwintered in the lotus roots, weed roots, or soil. The population dynamics of H. diversa in lotus roots in paddy fields determined in this study will be useful for development of control strategies.
  2019年11月, 研究論文（学術雑誌）, 共同, 54, 4, 0003-6862, DOI(公開)(r-map), 465, 471
• Relation between climatic factors and the status of active aluminum of Andosols in the Kuju Plateau, Japan and effect of surface soil acidity on the early growth of Italian ryegrass.
  Noriko Yamaguchi, Hideo Kubotera, Takashi Kusaba, Takeo Shima, Yasuhisa Masuda, So Sakai, Katsuhiko Tsuruoka, and Koki Toyota
  Pedologists
  2019年09月, 研究論文（学術雑誌）, 共同, 63, 2, DOI(公開)(r-map), 82, 93
• Effects of inoculation with a commercial microbial inoculant Bacillus subtilis C-3102 mixture on rice and barley growth and its possible mechanism in the plant growth stimulatory effect
  Abdul Saleem Jamily1, Yuki Koyama1, Thida Aye Win1, Koki Toyota1*, Seiya Chikamatsu1, Takeshi Shirai2, Taisuke Uesugi2, Hiroaki Murakami2, Tetsuya Ishida2, Takaomi Yasuhara2
  Journal of Plant Protection Research
  2019年06月28日, 研究論文（学術雑誌）, 共同, 59, 2, DOI(公開)(r-map)
• Yu Yu Min and Koki Toyota
  Occurrence of Different Kinds of Diseases in Sesame Cultivation in Myanmar and Their Impact to Sesame Yield
  Journal of Experimental Agriculture International
  2019年06月, 研究論文（学術雑誌）, 共同, 38, 4, 1, 9
• Application of Biogas Digestate with Rice Straw Mitigates Nitrate Leaching Potential and Suppresses Root-Knot Nematode (Meloidogyne incognita)
  Wang, Yuexi; Chikamatsu, Seiya; Gegen, Tuya; Sawada, Kozue; Toyota, Koki; Riya, Shohei; Hosomi, Masaaki
  AGRONOMY-BASEL
  MDPI
  This study investigated the effects of biogas digestate application to soil with rice straw on nitrate leaching potential and nematicidal activity toward root-knot nematodes Meloidogyne incognita. The following seven treatments were set up: (i) control (CONT); (ii) chemical fertilizer (CF); (iii) wet biogas digestate derived from pig manure (WBD); (iv) and (v) dry biogas digestate derived from a mixture of pig manure and rice straw at an initial C/N ratio of 20 and 30 (DBD20 and DBD30); (vi) and (vii) DBD20 mixed with rice straw to adjust the C/N ratio to 16 (Mix1) and 30 (Mix2), respectively. The application rate of CF and digestates was adjusted to 200 mg N kg(-1) soil based on the inorganic ammonium nitrogen contents. Nitrate contents readily increased in all the treatments with incubation, except for Mix2, and those at day 90 were decreased with increasing initial labile C contents. Garden balsam was grown as a test plant for root-knot nematodes using the soils at day 90 and the results showed that the gall index was significantly lower in Mix2 and Mix1 than in CF. These results suggest that dry digestate mixed with rice straw might have potential for lower nitrate leaching and nematicidal properties.
  2019年05月10日, 研究論文（学術雑誌）, 共同, 9, 5, DOI(公開)(r-map), 227
• 白井　さよ・豊田　剛己
  ダイズ・エダマメのセンチュウ害　診断と防除の取組
  土つくりとエコ農業
  2019年05月, 研究論文（その他学術会議資料等）, 共同
• Nguyen Thi Kim Phuong, Chau Minh Khoi, Nguyen Van Sinh, Nguyen Huu Chiem and Koki Toyota
  Effects of Rice Husk Biochar and Calcium Amendment on Remediation of Saline Soil from Rice-shrimp Cropping System in Vietnamese Mekong Delta
  Journal of Experimental Agriculture International
  2019年05月, 研究論文（学術雑誌）, 共同, 39, 2, 1, 12
• 河野辺　雅徳・豊田　剛己
  沖縄のキク畑における植物寄生性線虫について
  土つくりとエコ農業
  2019年03月, 研究論文（その他学術会議資料等）, 共同
• Nematicidal activity of fipronil against the root-lesion nematode, Pratylenchus zeae, in sugarcane roots under field environment.
  Masanori Kawanobe, Koki Toyota, Takashi Seko and Koshi Gunjima
  Journal of Nematology
  2019年02月, 研究論文（学術雑誌）, 共同, 51, 1, DOI(公開)(r-map), 1, 14
• Optimisation of a species-specific primer set to quantify the soybean cyst nematode, Heterodera glycines, in soil using real-time PCR
  Shirai, Sayo; Toyota, Koki
  NEMATOLOGY
  BRILL ACADEMIC PUBLISHERS
  We previously reported a real-time PCR primer set (SCN) that is specific to the soybean cyst nematode Heterodera glycines, a major nematode pest in soybean production in Japan. However, the primer set also amplified the related species H. trifolii and H. schachtii, whose presence was recently reported in Japan. The objective of this study was to optimise a primer set to be more specific for quantification of H. glycines. The newly optimised primer set (SCNnew) amplified H. trifolii and H. schachtii at amplification efficiencies less than 1% of H. glycines. Surveys for H. glycines in different green soybean fields in Japan demonstrated that most fields judged to contain low densities of H. glycines based on the SCN primer set were not actually infested with H. glycines. The SCNnew primer set quantifies H. glycines in soil more precisely.
  2019年01月, 研究論文（学術雑誌）, 共同, 21, 10, 1388-5545, DOI(公開)(r-map), 1037, 1042
• Relationship among the potato rot nematode, Ditylenchus destructor, densities in soil, root and garlic (Allium sativum) bulbs, and rot damage in stored garlic bulbs
  Cheng, Zejun; Toyota, Koki; Aoyama, Rie
  NEMATOLOGY
  BRILL ACADEMIC PUBLISHERS
  The potato rot nematode, Ditylenchus destructor, threatens garlic production in Japan. The objectives of this study were to determine the relationships of D. destructor densities in soil, garlic roots and outer skins of garlic bulbs, and damage to bulbs that rot during storage. Ditylenchus destructor densities were evaluated with the real-time PCR method. There was a significant positive correlation between D. destructor densities in soil at planting and those in the outer skin of garlic bulbs at harvest in 2016, but not in 2017. Ditylenchus destructor densities in outer skins at harvest were consistently low when those in roots at harvest were lower than 80 ind. (0.05 g)(-1). No damage to garlic bulbs after storage was observed when D. destructor densities in outer skins were lower than 300 ind. (0.05 g)(-1). These results indicate that D. destructor densities in roots and outer skins may be a good indicator to estimate nematode damage to garlic bulbs after storage.
  2019年01月, 研究論文（学術雑誌）, 共同, 21, 5, 1388-5545, DOI(公開)(r-map), 547, 555
• Masanori Kawanobe, Koki Toyota, Hidehito Uchihara and Mikoto Takae
  Developing a real-time PCR diagnostic method for a potential threat to chrysanthemum, Paratylenchus dianthus
  JOURNAL OF NEMATOLOGY
  2019年, 研究論文（学術雑誌）, 共同, 51, DOI(公開)(r-map), e2019-43
• Growing Interest in Microbiome Research Unraveling Disease Suppressive Soils against Plant Pathogens
  Koki Toyota1 and Sayo Shirai
  Microbes and Environments
  2018年12月, 研究論文（学術雑誌）, 共同, 33, 4, DOI(公開)(r-map), 345, 347
• A case study on a modified method to quantify the density of some soil-borne plant-parasitic nematodes in a simpler and less expensive way
  Zejun Cheng, Sayo Shirai, Koki Toyota and Karl Ritz
  Nematological Research
  2018年10月, 研究論文（学術雑誌）, 共同, 48, 1, DOI(公開)(r-map), 11, 17
• Application of a simple and high-throughput DNA extraction method to real-time PCR quantification of target plant-parasitic nematodes in nematode communities
  Masanori Kawanobe and Koki Toyot
  Nematolotogical Research
  2018年10月, 研究論文（学術雑誌）, 共同, 48, 1, DOI(公開)(r-map), 1, 10
• Effect of solarization on the density of Fusarium oxysporum in soil and the yield of lotus grown in Naruto area, Tokushima Prefecture, Japan
  Eiji Sawada, Yuki Koyama, Taizo Sato, Kengo Yonemoto and Koki Toyota
  Soil Microorganisms
  2018年04月, 研究論文（学術雑誌）, 共同, 72, 1, 34, 38
• Isolation of local Bacillus spp. from Afghanistan soils and their potential in suppressing the root-knot nematodes on tomato
  Abdul Saleem Jamily, Koki Toyota and Yuki Koyama
  Soil Microorganisms
  2018年04月, 研究論文（学術雑誌）, 共同, 72, 1, 39, 49
• Plant-parasitic nematodes in some economically important crops in Myanmar ; species, possible damage and control measures
  Yu Yu MIN and Koki TOYOTA
  Nematology
  2018年01月, 研究論文（学術雑誌）, 共同, 20, 1, DOI(公開)(r-map), 1, 3
• 北大東島の赤黄色土における糖蜜施用がサトウキビの生育・収量および土壌化学性に及ぼす影響
  吉田晃一・宮丸直子・川中岳志・大城浩照・橋本洋平・豊田剛己
  日本土壌肥料学雑誌
  2017年12月, 研究論文（学術雑誌）, 共同, 88, 6, 509, 518
• Bacterial Degraders of Coexisting Dichloromethane, Benzene, and Toluene, Identified by Stable-Isotope Probing
  Yoshikawa, Miho; Zhang, Ming; Kurisu, Futoshi; Toyota, Koki
  WATER AIR AND SOIL POLLUTION
  SPRINGER
  Most bioremediation studies on volatile organic compounds (VOCs) have focused on a single contaminant or its derived compounds and degraders have been identified under single contaminant conditions. Bioremediation of multiple contaminants remains a challenging issue. To identify a bacterial consortium that degrades multiple VOCs (dichloromethane (DCM), benzene, and toluene), we applied DNA-stable isotope probing. For individual tests, we combined a C-13-labeled VOC with other two unlabeled VOCs, and prepared three unlabeled VOCs as a reference. Over 11 days, DNAwas periodically extracted from the consortia, and the bacterial community was evaluated by next-generation sequencing of bacterial 16S rRNA gene amplicons. Density gradient fractions of the DNA extracts were amplified by universal bacterial primers for the 16S rRNA gene sequences, and the amplicons were analyzed by terminal restriction fragment length polymorphism (T-RFLP) using restriction enzymes: HhaI and MspI. The T-RFLP fragments were identified by 16S rRNA gene cloning and sequencing. Under all test conditions, the consortia were dominated by Rhodanobacter, Bradyrhizobium/Afipia, Rhizobium, and Hyphomicrobium. DNA derived from Hyphomicrobium and Propioniferax shifted toward heavier fractions under the condition added with C-13-DCM and C-13-benzene, respectively, compared with the reference, but no shifts were induced by C-13-toluene addition. This implies that Hyphomicrobium and Propioniferax were the main DCM and benzene degraders, respectively, under the coexisting condition. The known benzene degrader Pseudomonas sp. was present but not actively involved in the degradation.
  2017年11月, 研究論文（学術雑誌）, 共同, 228, 11, 0049-6979, DOI(公開)(r-map)
• Effect of short-term growth of mung bean and its soil incorporation on the density of the soybean cyst nematode, Heterodera gly
  Seiya CHIKAMATSU, Wang XIAOMAN, Daisuke ITO, Emi YAMADA and Koki TOYOTA
  Nematology
  2017年11月, 研究論文（学術雑誌）, 共同, 19, 10, 1147, 1155
• Biodegradation of Volatile Organic Compounds and Their Effects on Biodegradability under Co-Existing Conditions
  Yoshikawa, Miho; Zhang, Ming; Toyota, Koki
  MICROBES AND ENVIRONMENTS
  JAPANESE SOC MICROBIAL ECOLOGY, DEPT BIORESOURCE SCIENCE
  Volatile organic compounds (VOCs) are major pollutants that are found in contaminated sites, particularly in developed countries such as Japan. Various microorganisms that degrade individual VOCs have been reported, and genomic information related to their phylogenetic classification and VOC-degrading enzymes is available. However, the biodegradation of multiple VOCs remains a challenging issue. Practical sites, such as chemical factories, research facilities, and illegal dumping sites, are often contaminated with multiple VOCs. In order to investigate the potential of biodegrading multiple VOCs, we initially reviewed the biodegradation of individual VOCs. VOCs include chlorinated ethenes (tetrachloroethene, trichloroethene, dichloroethene, and vinyl chloride), BTEX (benzene, toluene, ethylbenzene, and xylene), and chlorinated methanes (carbon tetrachloride, chloroform, and dichloromethane). We also summarized essential information on the biodegradation of each kind of VOC under aerobic and anaerobic conditions, together with the microorganisms that are involved in VOC-degrading pathways. Interactions among multiple VOCs were then discussed based on concrete examples. Under conditions in which multiple VOCs co-exist, the biodegradation of a VOC may be constrained, enhanced, and/ or unaffected by other compounds. Co-metabolism may enhance the degradation of other VOCs. In contrast, constraints are imposed by the toxicity of co-existing VOCs and their by-products, catabolite repression, or competition between VOC-degrading enzymes. This review provides fundamental, but systematic information for designing strategies for the bioremediation of multiple VOCs, as well as information on the role of key microorganisms that degrade VOCs.
  2017年09月, 研究論文（学術雑誌）, 共同, 32, 3, 1342-6311, DOI(公開)(r-map), 188, 200
• Bacterial degraders of coexisting dichloromethane, benzene and toluene, identified by stable-isotope probing
  Miho Yoshikawa, Ming Zhang, Futoshi Kurisu and Koki Toyota
  Water, Air, and Soil Pollution
  2017年03月, 研究論文（学術雑誌）, 共同, 228, 418
• Integrated Anaerobic-Aerobic Biodegradation of Multiple Contaminants Including Chlorinated Ethylenes, Benzene, Toluene, and Dichloromethane
  Yoshikawa, Miho; Zhang, Ming; Toyota, Koki
  WATER AIR AND SOIL POLLUTION
  SPRINGER
  Complete bioremediation of soils containing multiple volatile organic compounds (VOCs) remains a challenge. To explore the possibility of complete bioremediation through integrated anaerobic-aerobic biodegradation, laboratory feasibility tests followed by alternate anaerobic-aerobic and aerobic-anaerobic biodegradation tests were performed. Chlorinated ethylenes, including tetrachloroethylene (PCE), trichloroethylene (TCE), cis-dichloroethylene (cis-DCE), and vinyl chloride (VC), and dichloromethane (DCM) were used for anaerobic biodegradation, whereas benzene, toluene, and DCM were used for aerobic biodegradation tests. Microbial communities involved in the biodegradation tests were analyzed to characterize the major bacteria that may contribute to biodegradation. The results demonstrated that integrated anaerobic-aerobic biodegradation was capable of completely degrading the seven VOCs with initial concentration of each VOC less than 30 mg/L. Benzene and toluene were degraded within 8 days, and DCM was degraded within 20 to 27 days under aerobic conditions when initial oxygen concentrations in the headspaces of test bottles were set to 5.3% and 21.0%. Dehalococcoides sp., generally considered sensitive to oxygen, survived aerobic conditions for 28 days and was activated during the subsequent anaerobic biodegradation. However, degradation of cis-DCE was suppressed after oxygen exposure for more than 201 days, suggesting the loss of viability of Dehalococcoides sp., as they are the only known anaerobic bacteria that can completely biodegrade chlorinated ethylenes to ethylene. Anaerobic degradation of DCM following previous aerobic degradation was complete, and yet-unknown microbes may be involved in the process. The findings may provide a scientific and practical basis for the complete bioremediation of multiple contaminants in situ and a subject for further exploration.
  2017年01月, 研究論文（学術雑誌）, 共同, 228, 1, 0049-6979, DOI(公開)(r-map)
• Integrated Anaerobic-Aerobic Biodegradation of Multiple Contaminants Including Chlorinated Ethylenes, Benzene, Toluene, and Dichloromethane
  Miho Yoshikawa, Ming Zhang and Koki Toyota
  Water, Air, and Soil Pollution
  2017年01月, 研究論文（学術雑誌）, 共同, 228, 25
• Effect of Heterodera glycines and soil chemical and biological cultivation factors on the yield of green soybean grown in a glasshouse in Japan
  Ito, Daisuke; Toyota, Koki; Li, Zhen Guang
  Nematology
  BRILL ACADEMIC PUBLISHERS
  Yellowing symptoms sometimes cause yield losses in green soybean cultivation. The objective of this study was to estimate the yield loss factors in a glasshouse. The parameters evaluated were plant-parasitic nematodes (Heterodera glycines, Pratylenchus penetrans, Meloidogyne spp.) and soil chemical properties. While the density of H. glycines did not show a negative correlation with yield in the February planting date, it showed a strongly negative correlation in the March planting date. Multiple regression analysis showed that yield was significantly correlated with P. penetrans and nitrate in the February planting, and with H. glycines and K in the March planting. The present study revealed that yield loss was caused by P. penetrans and nitrate in seasons with unsuitable temperatures for H. glycines hatch, and by H. glycines and alleviated by K in seasons with optimum temperatures for H. glycines hatching.
  2017年, 研究論文（学術雑誌）, 共同, 19, 2, 1388-5545, DOI(公開)(r-map), 237, 244
• Low nitrogen availability and shallow plow layer decrease sugarcane productivity in Kitadaito Island, Japan
  Koichi YOSHIDA, Naoko MIYAMARU, Takeshi KAWANAKA, Yohey HASHIMOTO, Koki TOYOTA
  Soil Science and Plant Nutrition
  2016年12月, 研究論文（学術雑誌）, 共同, 62, 5-6, 504, 510
• Enhancement and biological characteristics related to aerobic biodegradation of toluene with co-existence of benzene
  Miho Yoshikawa, Ming Zhang and Koki Toyota
  Water, Air, & Soil Pollution
  2016年09月, 研究論文（学術雑誌）, 共同, 227, 340
• A field experiment with nematicide treatment revealed potential sugarcane yield loss caused by plant-parasitic nematodes in Okinawa, Japan
  Masanori Kawanobe, Naoko Miyamaru, Koichi Yoshida, Takeshi Kawanaka and Koki Toyota
  Nematological Research
  2016年07月, 研究論文（学術雑誌）, 共同, 46, 1, 1, 8
• Development of a quantification method with real-time PCR for three Pratylenchus species causing damage to chrysanthemum in Japan
  Yuki Koyama, Koki Toyota, Naoko Miyamaru, Koichi Yoshida and Kenta Uesugi
  Nematology
  2016年06月, 研究論文（学術雑誌）, 共同, 18, 6, 687, 695
• Development of real-time PCR primers for the quantification of Meloidogyne graminicola, Hirschmanniella oryzae and Heterodera cajani, the pests of the major crops in Myanmar
  Akane Katsuta, Koki Toyota, Yu Yu Min and The Thiri Maung
  Nematology
  2016年03月, 研究論文（学術雑誌）, 共同, 18, 3, 257, 263
• Effect of two whole crop rice cultivars on methane emission and Cu and Zn uptake in a paddy field fertilized with biogas slurry
  Aye Thida Wina, Koki Toyota, Daisuke Ito, Seiya Chikamastu, Takashi Motobayashi, Natsuko Takahashi, Taiichiro Ookawa, Tadashi Hirasawa
  Soil Science and Plant Nutrition
  2016年02月, 研究論文（学術雑誌）, 共同, 62, 1, 99, 105
• Potential nitrogen immobilization as influenced by available carbon in Japanese arable and forest soils
  Kozue Sawada, Shinya Funakawa, Koki Toyota and Takashi Kosaki
  Soil Science and Plant Nutrition
  2015年12月, 研究論文（学術雑誌）, 共同, 61, 6, 917, 926
• Development of real-time PCR primers specific to the potato rot nematode Ditylenchus destructor causing damage to garlic to quantify its density in soil
  Zejun Cheng, Koki Toyota, Kazuo Yamashita
  Nematological Research
  2015年12月, 研究論文（学術雑誌）, 共同, 45, 2
• A real-time PCR-based assay for potential risk of Meloidogyne incognita
  Yuki Koyama, Chikako Mihara, Yuso Kobara, Noriaki Momma and Koki Toyota
  Nematological Research
  2015年12月, 研究論文（学術雑誌）, 共同, 45, 2
• 土壌病害と有機物施用
  豊田剛己・宮原麻岐・吉原周佑・兒山裕貴・勝田あかね・Saleem Jamily・宮崎駿人
  土と微生物
  2015年10月, 共同, 69, 2, 31, 34
• Bacillus-related Spore Formers: Attractive Agents for Plant Growth Promotion
  Koki Toyota
  Microbes and Environments
  2015年09月, 単独, 30, 3, 205, 207
• Influence of nematicide on the damage caused by Meloidogyne incognita to sweet potato in sandy fields in northeastern Tokushima prefecture
  Naruhito Abe, Masanori Matsuzaki, Kentaro Wada, Akio Nakano, Erika Sato, Gen Hattori, Koki Toyota
  Applied Entomology and Zoology
  2015年05月, 研究論文（学術雑誌）, 共同, 50, 2, 255, 261
• Suppression of the soybean cyst nematode, Heterodera glycines, using water extract of bean sprout residue
  Daisuke Ito, Koki Toyota and Ghalia Missous Sedrati
  Nematology
  2015年05月, 研究論文（学術雑誌）, 共同, 17, 5, 523, 530
• Quantification of lesion nematode (Pratylenchus zeae), stunt nematode (Tylenchorhynchus leviterminalis), spiral nematode (Helicotylenchus dihystera) and lance nematode (Hoplolaimus columbus), parasites of sugarcane in Kitadaito, Okinawa, Japan, using real-time PCR
  Masanori Kawanobe, Naoko Miyamaru, Koichi Yoshida, Takeshi Kawanaka, Koki Toyota
  Nematological Research
  2015年04月, 研究論文（学術雑誌）, 共同, 45, 1, 35, 44
• Characterization of possible bacterial biocontrol agents, isolated from various plants in Indonesia, against bacterial wilt and damping-off of tomato
  Yuliar, Koki Toyota, Kenji Yokota
  Soil Microorganisms
  2015年04月, 研究論文（学術雑誌）, 共同, 69, 1, 39, 47
• 拮抗細菌の接種および前作栽培作物の種類がトマト青枯病発病抑制効果に及ぼす影響
  須賀有子・井川岳士・豊田剛己
  日本土壌肥料学雑誌
  2015年04月, 研究論文（学術雑誌）, 共同, 86, 2, 98, 102
• Effects of water saving irrigation and rice variety on CH4 and N2O emissions from a Japanese paddy field fertilized with acidified anaerobically digested pig slurry
  Khin Thawda WIN, Ryoko NONAKA, Aye Thida WIN, Yu Sasada, Koki TOYOTA, Takashi MOTOBAYASHI and Masaaki HOSOMI
  Paddy and Water Environment
  2015年03月, 研究論文（学術雑誌）, 共同, 13, 1, 51, 60
• Recent trends in the control methods for bacterial wilt diseases caused by Rasltonia solanacerum
  Yuliar, Yanetri Asi Nion, Koki Toyota
  Microbes and Environments
  2015年03月, 共同, 30, 1, 1, 11
• Effects of the application of digestates from wet and dry anaerobic fermentation to Japanese paddy and upland soils on short-term nitrification
  Kozue Sawada, Koki Toyota
  Microbes and Environments
  2015年03月, 研究論文（学術雑誌）, 共同, 30, 1, 37, 43
• 堆肥をはじめとする各種有機質資材による土壌生物機能の向上
  豊田剛己
  肥料科学
  2015年02月, 単独, 36, 27, 42
• Effect of biogas slurry application on CH4 and N2O emissions, Cu and Zn uptakes by whole crop rice in a paddy field in Japan.
  Aye Thida Win, Khin Thawda Win, Yu Sasada, Koki Toyota, Takashi Motobayashi, Taiichiro Ookawa, Tadashi Hirasawa, Chen Dingjiang and Jun Lu
  Soil Science and Plant Nutrition
  2014年12月, 研究論文（学術雑誌）, 共同, 60, 6, 411, 422
• すべてがわかる夢の土壌診断へ
  豊田剛己
  土と微生物
  2014年10月, 単独, ６８, ２, ６２－６４
• Plant-parasitic nematodes in sugarcane fields in Kitadaito Island (Okinawa), Japan, as a potential sugarcane growth inhibitor
  Masanori Kawanobe, Naoko Miyamaru, Koichi Yoshida, Takeshi Kawanaka and Koki Toyota
  Nematology
  2014年07月, 研究論文（学術雑誌）, 共同, 16, 7, 807, 820
• Recent trends in microbial inoculants in agriculture.
  Toyota, K. and Watanabe, T.
  Microbes and Environments
  2013年12月, 共同, 28, 4, 403, 404
• Development of a direct quantitative detection method for Meloidogyne incognita and M. hapla in andosol and analysis of relationship between the initial population of Meloidogyne spp. and yield of eggplant
  Takayoshi Watanabe, Hiroaki Masumura, Yuzo Kioka, Katsunori Noguchi, Yu Yu Min, Risa Murakami and Koki Toyota
  Nematological Research
  2013年12月, 研究論文（学術雑誌）, 共同, 43, 2, 21, 30
• 軽石培地を用いた養液栽培における拮抗菌およびリジンやシュクロースの添加がトマトの根面微生物群集および青枯病発病に及ぼす影響
  須賀有子・井川岳士・Yanetri Asi Nion・豊田剛己
  土と微生物
  2013年10月, 研究論文（学術雑誌）, 共同, 67, 2
• Effects of continuous lily cultivation on the fungal community structure in cedar bark media
  Yuko Suga, Kazuhiko Takagi, Yasufumi Kuroda, Koki Toyota
  Soil Microorganisms
  2013年10月, 研究論文（学術雑誌）, 共同, 67, 2
• Nitrogen dynamics of anaerobically digested slurry used to fertilize paddy fields
  Dingjiang Chen, Lina Jiang, Hong Huang, Koki Toyota, Randy A. Dahlgren, Jun Lu
  Biology and Fertility of Soils
  2013年08月, 研究論文（学術雑誌）, 共同, 49, 6, 647, 659
• Effects of the density of root-lesion nematode (Pratylenchus penetrans), soil chemical and microbial properties on the damage to Japanese radish
  Erika Sato, Ichi Okumura, Yoshihiro Kokatsu, Koki Toyota
  Nematology
  2013年08月, 研究論文（学術雑誌）, 共同, 15, 8, 931, 938
• Effect of bean sprout residue on the hatching and density of the soybean cyst nematode Heterodera glycines in soil
  Koki TOYOTA, Keita GOTO and Daisuke ITO
  Nematology
  2013年08月, 研究論文（学術雑誌）, 共同, 15, 8, 923, 927
• Development of specific primers to Hirschmanniella spp. causing damage to lotus and their economical threshold level in Tokushima prefecture in Japan
  Yuki KOYAMA, So Pyay THAR, Chihiro KIZAKI, Koki TOYOTA, Eiji SAWADA and Naruhito ABE
  Nematology
  2013年07月, 研究論文（学術雑誌）, 共同, 15, 7, 851, 858
• 土壌微生物研究におけるモデル基質としてのグルコース利用ー研究事例と今後の展望ー
  沢田こずえ・豊田剛己
  土と微生物
  2013年04月, 共同, 67, 1, 32, 38
• リアルタイム定量PCRによる土壌微生物の特異的・定量的検出
  佐藤恵利華・豊田剛己
  土と微生物
  2013年04月, 共同, 67, 1, 26, 31
• Decrease in fungal biodiversity along an available phosphorous gradient in arable Andosol soils in Japan
  Zhihua Bao, Yuko Matsushita, Sho Morimoto, Yuko Takada Hoshino, Chika Suzuki, Kazunari Nagaoka, Makoto Takenaka, Hiroharu Murakami, Yukiko Kuroyanagi, Yasufumi Urashima, Hiroyuki Sekiguchi, Atsuhiko Kushida, Koki Toyota, Masanori Saito, and Seiya Tsushima
  Canadian Journal of Microbiology
  2013年04月, 研究論文（学術雑誌）, 共同, 59
• Suppressiveness of Meloidogyne incognita in different agricultural soils and possible contribution of soil fauna
  Yu Yu Min, Koki Toyota
  Nematology
  2013年04月, 研究論文（学術雑誌）, 共同, 15, 4, 459, 468
• 土壌燻蒸剤は本当に皆殺し剤なのか
  豊田剛己
  農薬時代
  2013年03月, 単独, 194, 22, 27
• Phyto-purification of livestock-derived organic waste by forage rice under subtropical climate.
  Kei Asada, Taku Nishimura, Chihiro Kato, Koki Toyota, Masaaki Hosomi
  Paddy and Water Environment
  2013年01月, 研究論文（学術雑誌）, 共同, 11, 1-4, 559, 571
• Comparison of methanotrophic bacteria, methane oxidation activity and methane emission in rice fields fertilized with anaerobically digested slurry between a fodder rice and a normal rice variety
  K.T. Win, R. Nonaka, A.T. Win, Y. Sasada, K. Toyota, T. Motobayashi and M. Hosomi
  Paddy and Water Environment
  2012年12月, 研究論文（学術雑誌）, 共同, 10, 4, 281, 289
• 緑肥と堆肥の連用がジャーガルの各種性質に及ぼす影響
  宮丸直子・伊波聡・儀間靖・亀谷茂・豊田剛己
  日本土壌肥料学雑誌
  2012年06月, 研究論文（学術雑誌）, 共同, 83, 3, 280, 287
• A novel nematode diagnostic method by the direct quantification of plant-parasitic nematodes in soil with real-time PCR
  Yu Yu Min, Koki Toyota and Erika Sato
  Nematology
  2012年03月, 研究論文（学術雑誌）, 共同, 14, 3, 265, 276
• Decontamination of anaerobically digested slurry in a paddy field ecosystem in Jiaxing region of China
  Lu J, Jiang LN, Chen DJ, Toyota K, Strong PJ, Wang HL, Hirasawa T
  Agriculture, Ecosystems & Environment
  2012年01月, 研究論文（学術雑誌）, 共同, 146, 1, 13, 22
• Environmental impact in a whole crop rice cultivation fertilized with anaerobically digested cattle or pig slurry
  Yu Sasada, Khin Thawda Win, Ryoko Nonaka, Aye Thida Win, Koki Toyota, Takashi Motobayashi, Chen Dingjiang and Jun Lu
  Biology and Fertility of Soils
  2011年11月, 研究論文（学術雑誌）, 共同, 47, 8, 948, 956
• 発病抑止土壌に関する最近の研究動向
  豊田剛己
  土作りとエコ農業
  2011年10月, 単独, 43, 10/11, 31, 38
• High labile organic matter and low available nitrogen is related to low productivity in soils of Daito Islands
  Naoko Miyamaru, Satoru Iha, Yasushi Gima and Koki Toyota
  Soil Microorganisms
  2011年10月, 研究論文（学術雑誌）, 共同, 65, 2, 119, 124
• Effect of anaerobically digested slurry on damages caused by the root-knot nematode to tomato and by the root-lesion nematode to radish
  Yu Yu Min, Koki Toyota, Sato Erika and Atsushi Takda
  Applied and Environmental Soil Science
  2011年06月, 研究論文（学術雑誌）, 共同, 2011, Article ID 528712
• A multiplex real-time PCR assay for the simultaneous quantification of the major plant parasitic nematodes in Japan
  Keita Goto, Yu Yu Min, Erika Sato and Koki Toyota
  Nematology
  2011年06月, 研究論文（学術雑誌）, 共同, 13, 6, 713, 720
• Changes in microbial functional diversity and activity in paddy soils irrigated with industrial wastewater in Bandung, West Java Province, Indonesia
  Siti Khodijah Chaerun, Nurmi P. D. Pangesti, Koki Toyota and William B. Whitman
  Water Air and Soil Pollution
  2011年05月, 研究論文（学術雑誌）, 共同, 217, 491, 502
• Quantification of Pratylenchus penetrans in radish fields using a combination method of soil compaction and real-time PCR to determine the economic threshold
  Erika SATO, Yuko SUGA, Chihiro KISAKI, Koki TOYOTA, Kazuto MIYAKE, Atsushi TAKADA, Koji TAKEUCHI and Rie MATSUURA
  Soil Science and Plant Nutrition
  2011年04月, 研究論文（学術雑誌）, 共同, 57, 2, 213, 220
• Difference of soil biological responses to amendment with okara and coffee residue compost or cow manure compost
  Erika Sato, Koki Toyota, Hajime Takeda and Ichi Okumura
  Soil Microorganisms
  2011年04月, 研究論文（学術雑誌）, 共同, 65, 1, 18, 26
• Effect of the nematicide imicyafos on soil nematode community structure and damage to radish by Pratylenchus penetrans
  Satoko Wada and Koki Toyota
  Journal of Nematology
  2011年03月, 研究論文（学術雑誌）, 共同, 43, 1, 1, 6
• 農薬による土壌微生物の活動制御
  豊田剛己・Khin Moe Kyaw
  日本農薬学会誌
  2011年01月, 共同, 36, 1, 119, 123
• Development of a direct quantitative detection method of Meloidogyne incognita in sandy soils and its application to sweet potato cultivated fields in Tokushima prefecture, Japan
  Yu Yu Min, Koki Toyota, Keita Goto, Erika Sato, Shoko Mizuguchi, Naruhito Abe, Akio Nakano and Eiji Sawada
  Nematology
  2011年01月, 研究論文（学術雑誌）, 共同, 13, 1, 95, 102
• リアルタイムPCRを用いた土壌からの各種植物寄生性線虫の直接定量
  豊田剛己・佐藤恵利華・Yu Yu Min・後藤圭太
  植物防疫
  2010年11月, 共同, ６４, １１, 707, 712
• Comparison of calibration curves prepared by soil compaction or ball-mill method for the direct quantification of potato cyst nematode Globodera rostochiensis in soil
  Keita Goto, Erika Sato, Li Faung, Koki Toyota and Tomoko Sugito
  Nematological Research
  2010年10月, 研究論文（学術雑誌）, 共同, 40, 2, 41, 45
• 服部勉編「土壌微生物通信（1962-1986）探訪「過去との対話」（３）、「土壌微生物矛盾学講座」を考える　その２
  豊田剛己
  土と微生物、
  2010年10月, 単独, 64, 2, 123, 124
• Effects of option mitigating ammonia volatilization on CH4 and N2O emissions from a paddy field fertilized with anaerobically digested cattle slurry
  Khin Thawda WIN, Ryoko NONAKA, Koki TOYOTA, Takashi MOTOBAYASHI and Masaaki HOSOMI
  Biology and Fertility of Soils
  2010年08月, 研究論文（学術雑誌）, 共同, 46, 6, 589, 595
• Quantitative detection of Pratylenchus penetrans from soil using soil compaction and real-time PCR
  Erika Sato, Keita Goto, Yu Yu Min, Koki Toyota and Chika Suzuki
  Nematological Research
  2010年07月, 研究論文（学術雑誌）, 共同, 40, 1, 1, 6
• Soil microbial biomass phosphorus as an indicator of phosphorus availability in a Gleyic Andosols
  Tomoko Sugito, Koji Yoshida, Masako Takebe, Takuro Shinano and Koki Toyota
  Soil Science and Plant Nutrition,
  2010年06月, 研究論文（学術雑誌）, 共同, 56, 3, 390, 398
• Mechanism of tomato bacterial wilt suppression by the amendment of lysine to soil
  Marylene Bagarinao Posas and Koki Toyota
  Microbes and Environments
  2010年06月, 研究論文（学術雑誌）, 共同, 25, 2, 596, 605
• 「土壌微生物矛盾学講座」を考える
  豊田剛己
  服部勉編「土壌微生物通信（1962-1986）探訪（２）「通信」の時代と現在の間」
  2010年05月, 単独, 84, 97
• 微生物と土壌
  岡崎正規・木村園子ドロテア・波多野隆介・豊田剛己・林健太郎
  図説日本の土壌
  2010年04月, 共同, 46, 65
• メタン発酵消化液の飼料イネ栽培への適用
  豊田剛己・笹田優
  用水と廃水
  2010年01月, 共同, 52, 1, 69, 75
• 飼料イネ栽培へのメタン発酵消化液の多量投入が土壌，水質，大気環境に及ぼす影響
  須永薫子・吉村季織・侯紅・Khin Thawda WIN・田中治夫・吉川美穂・渡邊裕純・本林隆・加藤誠・西村拓・豊田剛己・細見正明
  日本土壌肥料学雑誌
  2009年12月, 研究論文（学術雑誌）, 共同, 80, 6, 596, 605
• Relationships between the damage to radish caused by the root-lesion nematode Pratylenchus penetrans, its density prior to cultivation and the soil nematode community structure evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis
  Erika Sato, Yu Yu MIN, Koki Toyota and Atsushi Takada
  Soil Science and Plant Nutrition
  2009年09月, 研究論文（学術雑誌）, 共同, 55, 4, 478, 484
• A novel detection method for the soybean cyst nematode Heterodera schactii using soil compaction and real-time PCR
  Keita Goto, Erika Sato and Koki Toyota
  Nematological Reseaech
  2009年06月, 研究論文（学術雑誌）, 共同, 39, 1, 1, 7
• Suppression of ammonia volatilization from a paddy soil fertilized with anaerobically digested cattle slurry by wood vinegar application and floodwater management
  Khin Thawda WIN, Koki TOYOTA, Takashi MOTOBAYASHI and Masaaki HOSOMI
  Soil Science and Plant Nutrition
  2009年02月, 研究論文（学術雑誌）, 共同, 55, 1, DOI(公開)(r-map)
• ミミズと土壌病害
  豊田剛己
  農業及び園芸
  2009年01月, 単独, 84, 1, 213, 218
• リアルタイムPCRによる植物寄生性線虫定量法の確立
  (25) 豊田剛己・佐藤恵利華・後藤圭太・白樫知明
  植物防疫
  2008年11月, 共同, 62, 11, 5, 9
• 土壌および養液栽培へのメタン消化液施用が数種土壌病害発生に及ぼす影響
  甘利誠・豊田剛己・Tajul MD Islam・増田和成・黒田哲生・渡辺昭
  土と微生物
  2008年10月, 研究論文（学術雑誌）, 共同, 62, 2, 106, 113
• Effect of different organic amendments on resistance and resilience of organic matter decomposing ability of soil and role of aggregated soil structure
  Chie Fujino, Satoko Wada, Tomohiko Konoike, Koki Toyota, Yuko Suga and Jun-ichi Ikeda
  Soil Science and Plant Nutrition
  2008年08月, 研究論文（学術雑誌）, 共同, 54, 4, 534, 542
• Analysis of the C2H2 inhibition-based N2O production curve to characterize the N2O-reducing activity of denitrifying communities in soil
  Yosuke Yanai, Ryusuke Hatano, Masanori Okazaki and Koki Toyota
  Geoderma
  2008年07月, 研究論文（学術雑誌）, 共同, 146, 1-2, 269, 276
• Suppression of bacterial wilt and Fusarium wilt by a Burkholderia nodosa strain isolated from Kalimantan soils, Indonesia
  Yanetri Asi Nion and Koki Toyota
  Microbes and Envrionments
  2008年06月, 研究論文（学術雑誌）, 共同, 23, 2, 134, 141
• 1,3－ジクロロプロペン，クロルピクリン及び太陽熱による土壌消毒がセルロース分解能及び硝化菌に及ぼす影響
  和田さと子・藤野智絵・豊田剛己・岡本保
  土と微生物
  2008年04月, 研究論文（学術雑誌）, 共同, 62, 1, 21, 31
• 養液栽培へのリジンおよび拮抗菌の添加がトマト青枯病に及ぼす影響
  井川岳士・井出磨美・Yanetri Asi Nion・豊田剛己・黒田哲生・増田和成
  土と微生物
  2008年04月, 研究論文（学術雑誌）, 共同, 62, 1, 9, 15
• Development of a real-time PCR method for the potato cyst nematode Globodera rostochiensis and the root-knot nematode Meloidogyne incognita
  (76) Koki TOYOTA, Tomoaki SHIRAKASHI, Erika SATO, Satoko WADA, Yu Yu MIN
  Soil Science and Plant Nutrition
  2008年02月, 研究論文（学術雑誌）, 共同, 54, 1, 72, 76
• Fungal N2O production in an arable peat soil in central Kalimantan, Indonesia
  Yanai, Yosuke, Toyota, Koki, Morishita, Tomoaki, Takakai, Fumiaki, Hatano, Ryusuke, Limin, Suwido H., Darung, Untung, Dohong, Salampak
  Soil Science and Plant Nutrition
  2007年12月, 研究論文（学術雑誌）, 共同, 53, 6, 806, 811
• Suppressive effect of anaerobically digested slurry on the root lesion nematode Pratylenchus penetrans and its potential mechanisms
  Yu Yu Min, Erika Sato, Tomoaki Shirakashi, Satoko Wada, Koki Toyota and Akira Watanabe
  Japanese Journal of Nematology
  2007年12月, 研究論文（学術雑誌）, 共同, 37, 2, 93, 100
• Detection of the root-lesion nematode, Pratylenchus penetrans, from a nematode community using real-time PCR
  Erika Sato, MinYu Yu, Tomoaki Shirakashi, Satoko Wada and Koki Toyota
  日本線虫学会誌
  2007年12月, 研究論文（学術雑誌）, 共同, 37, 2, 87, 92
• Response of denitrifying communities to successive soil freeze-thaw cycles.
  Yanai, Y., Toyota, K. and Okazaki, M.
  Biology and Fertility of Soils
  2007年10月, 研究論文（学術雑誌）, 共同, 44, 1, 113, 119
• Suppression of nitrous oxide production in soils applied with organic matter by the herbicides glyphosate and propanil.
  Khin Moe Kyaw and Koki Toyota
  Soil Science and Plant Nutrition
  2007年08月, 研究論文（学術雑誌）, 共同, 53, 4, 441, 447
• Ammonia emissions from anaerobically-digested slurry and chemical fertilizer applied to flooded forage rice
  (75) Hong Hou, Sheng Zhou, Masaaki Hosomi, Koki Toyota, Kiori Yosimura, Yuuko Mutou, Taku Nisimura, Masao Takayanagi and Takashi Motobayashi
  Water Air Soil Pollut
  2007年07月, 研究論文（学術雑誌）, 共同, 183, 37, 48
• Effects of charcoal addition on N2O emissions from soil resulting from rewetting air-dried soil in short-term laboratory experiments.
  Yanai Y, Toyota K, Okazaki M
  Soil Science and Plant Nutrition
  2007年04月, 研究論文（学術雑誌）, 共同, 53, 2, 181, 188
• Enhancement of Nitrogen-fixing Activity of Enterobacteriaceae Strains Isolated from Sago Palm (Metroxylon sagu) by Microbial Interaction with Non-nitrogen Fixers.
  Archana Shrestha, Koki Toyota, Masanori Okazaki, Yuko Suga, Marcelo A. Quevedo, Alan B. Loreto and Algerico A. Mariscal.
  Microbes and Environments
  2007年03月, 研究論文（学術雑誌）, 共同, 22, 1, 59, 70
• Repeated application of farmyard manure enhances resistance and resilience of soil biological functions against soil disinfection.
  Satoko Wada and Koki Toyota
  Biology and Fertility of Soils
  2007年01月, 研究論文（学術雑誌）, 共同, 43, 3, 349, 356
• Comparison of soil microbial community between soils amended with or without farmyard manure.
  Toyota, K. and Kuninaga, S.
  Applied Soil Ecology
  2006年08月, 研究論文（学術雑誌）, 共同, 33, 1, 39, 48
• Influence of application of rice straw, farmyard manure and municipal biowastes on nitrogen fixation, soil microbial biomass-N and mineral-N in a model paddy microcosm.
  Tanaka, H., Kyaw, K. M., Toyota, K. and Motobayashi, T.
  Biology and Fertility of Soils
  2006年08月, 研究論文（学術雑誌）, 共同, 42, 501, 505
• Improvement of the Traditional Sago Starch Processing in the Philippines Through Mechanization
  Alan B. LORETO, Marcelo A. QUEVEDO, Algerico M. MARISCAL, Masanori OKAZAKI and Koki TOYOTA:
  Sago Palm
  2006年07月, 研究論文（学術雑誌）, 共同, 14, 1, 4, 9
• Phylogenetic distribution of bacteria isolated from the floodwater of a Japanese paddy field.
  Natsuko Nakayama, Akiko Okabe, Koki Toyota, Makoto Kimura and Susumu Asakawa
  Soil Science and Plant Nutrition
  2006年06月, 研究論文（学術雑誌）, 共同, 52, 2, 305, 312
• Nitrogen fixing activity in different parts of sago palm (Metroxylon sagu) and characterization of aerobic nitrogen fixing bacteria colonizing sago palm.
  Archana Shrestha, Koki Toyota, Yoko Nakano, Masanori Okazaki, Marcelo Quevedo and Elsa I. Abayon
  Sago Palm
  2006年06月, 研究論文（学術雑誌）, 共同, 14, 1, 20, 32
• Phylogenetic distribution of bacteria isolated from the floodwater of a Japanese paddy field.
  Natsuko Nakayama, Akiko Okabe, Koki Toyota, Makoto Kimura and Susumu Asakawa.
  Soil Science and Plant Nutrition
  2006年04月, 研究論文（学術雑誌）, 共同, 52, 2, 305, 312
• PCR-DGGE法を用いた土壌線虫群集構造解析法の開発
  佐藤恵利華・豊田剛己
  日本土壌肥料学雑誌
  2006年04月, 研究論文（学術雑誌）, 共同, ７７, ２, 157, 163
• コーヒー粕堆肥連用土壌におけるトマト根腐萎凋病菌に対する高い静菌作用に関与する糸状菌の選抜。
  浜中康弘・豊田剛己・林（池田）恭子
  日本土壌肥料学雑誌（受理）
  2005年12月, 研究論文（学術雑誌）, 共同, 76, 6
• Nitrogen balance in a paddy field planted with whole crop rice (Oryza sativa cv. Kusahonami) during two rice-growing seasons.
  Khin Moe Kyaw, Koki Toyota, Masanori Okazaki, Takashi Motobayashi and Haruo Tanaka
  Biology and Fertility of Soils
  2005年11月, 研究論文（学術雑誌）, 共同, 42, 1, 72, 82
• 土壌中の遺伝子・遺伝子情報…何ができるのか、何がわかるのか。５．土壌微生物の群集構造解析（その１）DGGE、原理と畑土壌への適用。
  須賀有子・豊田剛己
  日本土壌肥料学雑誌
  2005年10月, 共同, 76, 5, 649, 655
• 土壌機能と微生物多様性
  和田さと子・豊田剛己・柳井洋介・大橋真理子：
  土と微生物
  2005年10月, 共同, ５９, ２, 91, 98
• シマミミズとお茶がらを用いた油汚染土壌の浄化促進。
  安智子・豊田剛己・白石祐彰
  Edaphologia
  2005年07月, 研究論文（学術雑誌）, 共同, 77, 1, 10
• モデル土壌中における土壌伝染性病原菌の個生態研究-ダイコン萎黄病菌とトマト青枯病菌を例に-
  豊田剛己
  土と微生物
  2005年04月, 単独, 59, 1, 45, 52
• 繰り返し栽培した軽石培地におけるトマト青枯病の発病抑制メカニズム
  松岡智生・豊田剛己・佐藤一朗・増田和成・黒田哲生
  土と微生物
  2005年04月, 研究論文（学術雑誌）, 共同, 59, 1, 15, 20
• 生ゴミ炭化物の土壌施用によるトマト青枯病抑制
  土と微生物
  2005年04月, 研究論文（学術雑誌）, 共同, 59, 1, 9, 14
• Predominant culturable Bacillus species in Japanese arable soils and their potential as biocontrol agents.
  Nishijima, T., Toyota, K. and Mochizuki, M.
  Microbes and Environments
  2005年03月, 研究論文（学術雑誌）, 共同, 20, 1, 61, 68
• バイオレメディエーション
  豊田剛己
  環境保全型農業事典
  2005年02月, 単独, 194, 197
• 土壌病害
  豊田剛己
  環境保全型農業事典
  2005年02月, 単独, 171, 176
• 土壌微生物
  豊田剛己
  環境保全型農業事典
  2005年02月, 単独, 152, 156
• 有機性廃棄物を利用した土壌病害防除
  豊田剛己
  再生と利用
  2004年12月, 単独, １０６, ６３－６８
• Comparison of disease suppressiveness of different soils with or without repeated application of organic matters to bacterial wilt of tomato caused by Ralstonia solanacearum.
  Satoh, K. and Toyota, K.
  Microbes and Environments
  2004年12月, 研究論文（学術雑誌）, 共同, 19, 4, 310, 314
• Effect of soil freeze-thaw-caused partial sterilization on nitrification potential in soil.
  Yanai, Y., Toyota, K. and Okazaki, M.
  Soil Science and Plant Nutrition
  2004年12月, 研究論文（学術雑誌）, 共同, 50, 6, 831, 837
• Effect of a successive soil freeze-thaw treatment on soil microbial biomass and organic matter decomposition potential of soil.
  Yanai, Y., Toyota, K. and Okazaki, M.
  Soil Science and Plant Nutrition
  2004年12月, 研究論文（学術雑誌）, 共同, 50, 6, 821, 829
• Effect of moisture conditions and pre-incubation at low temperature on bacterial wilt of tomato caused by Ralstonia solanacearum.
  Islam, MD. T. and Toyota, K.
  Microbes and Environments
  2004年09月, 研究論文（学術雑誌）, 共同, 19, 3, 244, 247
• Susceptibility of soils with or without repeated application of farmyard manure to bacterial wilt of tomato caused by Ralstonia solancearum.
  Tajul MD Islam and Toyota, K.
  土と微生物
  2004年04月, 研究論文（学術雑誌）, 共同, 58, 1, 33, 42
• 連作軽石のトマト青枯病抑制培地としての抑止力とその抑制メカニズム
  松岡智生・豊田剛己・増田和成・黒田哲生
  土と微生物
  2004年04月, 研究論文（学術雑誌）, 共同, 58, 1, 25, 32
• Suppression of bacterial wilt of tomato by Ralstonia solanacearum by incorporation of composts in soil and possible mechanisms.
  Tajul MD Islam and Toyota, K.
  Microbes and Environments
  2004年03月, 研究論文（学術雑誌）, 共同, 19, 1, 53, 60
• Effect of bensulfuron-methyl (a sulfonylurea herbicide) on soil bacterial community of a paddy soil microcosm.
  Saeki, M. and Toyota, K.
  Biology and Fertility of Soil
  2004年, 研究論文（学術雑誌）, 共同, 40, 2, 110, 118
• 除草剤ベンスルフロンメチルのモデル水田土壌における窒素固定能に及ぼす影響
  佐伯政男・豊田剛己
  日本土壌肥料学雑誌
  2003年12月, 研究論文（学術雑誌）, 共同, 74, 6, 809, 811
• 土壌の凍結融解反復処理が土壌微生物群集に及ぼす影響の調査事例
  柳井洋介・豊田剛己・岡崎正規
  土の微生物、57(1), 13-20
  2003年04月, 研究論文（学術雑誌）, 共同
• Functional characterization of soil microbial community based on utilization pattern of aromatic compounds.
  Marwati, U., Funasaka, K., Toyota, K. and Katayama, A.
  Soil Science and Plant Nutrition
  2003年02月, 研究論文（学術雑誌）, 共同, 49, 1, 143, 147
• Community structure of the microbiota associated with nodal roots of rice plants along with the growth stages: estimation by PCR-RFLP analysis.
  Ikenaga, M., Muraoka, Y., Toyota, K. and Kimura, M.
  Biology and Fertility of Soils
  2002年12月, 研究論文（学術雑誌）, 共同, 36, 6, 397, 404
• 土壌微生物モニタリングの現状と問題点
  長谷川周一・波多野隆介・岡崎正規編
  「環境負荷を予測する?モニタリングからモデリングへ?」、博友社、pp. 211-222
  2002年12月, 単独
• Tin concentrations in River/Bay sediments of Tokyo in 1984 and 2000.
  Baasansuren, J., Okazaki, M., Choi, I.-S. and Toyota, K.
  Soil Science and Plant Nutrition, 48(5), 667-672
  2002年10月, 共同
• 土壌生物、日本土壌肥料学会部門別進歩総説
  著者名：豊田剛己・岡紀邦・斎藤雅典
  日本土壌肥料学雑誌、73、629-635
  2002年10月, 共同
• Sago production and income analysis in northern Mindanao
  Celiz, L. L., Okazaki, M., Josue, A. R. and Toyota, K.
  Sago Palm, 10(1), 16-23
  2002年07月, 共同
• 厩肥を施用した農耕地断面における硝酸溶脱の実態例
  著者名：片山新太・山川晴義・水谷浩孝・井上康・豊田剛己・吉田重方
  環境科学会誌、15(4), 287-291
  2002年07月, 共同
• 土壌の有機物による汚染はこのようにして測れる。
  環境機器、106-109
  2001年12月, 単独
• 特許 特願2001-150207号、土壌病害を抑制するコーヒー粕堆肥
  2001年05月, 共同
• Autecology of Fusarium　 oxysporum f. sp. raphani in soil
  著者名：Toyota, K. and Kimura, M.
  Fusarium: Paul E. Nelson Memorial Symposium
  2001年03月, 共同
• Comparison of phospholipid fatty acid composition in floodwater and plow layer soil during the rice cultivation period in a Japanese paddy field.
  著者名：Okabe, A., Oike, H., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition46(4), 893-904
  2000年12月, 共同
• Microbiological factors affecting colonization of tomato roots by the bacterial wilt pathogen Ralstonia solanacearum YU1Rif43lux.
  著者名：Toyota, K., Kimura, M. and Kinoshita, T.
  Soil Science and Plant Nutrition46(3), 643-653
  2000年09月, 共同
• Observation on microbial colonization on the surface of rice roots along with their development and degradation.
  著者名：Muraoka, Y., Hamakawa, E., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition46(2),491-502
  2000年06月, 共同
• Suppression of Ralstonia solanacearum in soil following colonization by other strains of R. solanacearum.
  著者名：Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition46(2),　449-459
  2000年06月, 共同
• Microbial community indigenous to the earthworm Eisenia foetida
  著者名：Toyota, K. and Kimura, M.
  Biology and Fertility of Soils31(3/4), 187-190
  2000年05月, 共同
• 各種土壌消毒処理のメロンホモプシス根腐病への効果とそれに伴う土壌微生物群集の変化
  著者名：伊藤喜誠・豊田剛己・木村眞人
  日本土壌肥料学会誌71(2)
  2000年04月, 共同
• Comparison of microbial community structure among soils with different degree of susceptibility to Fusarium-wilt of radish.
  著者名：Toyota, K., Kimura, M., Takechi, S. and Kuninaga, S.
  Soil Microorganisms 54, 69-79
  2000年04月, 共同
• Seasonal variation of phospholipid fatty acid composition in the floodwater of a Japanese paddy field under a different fertilizer trial
  著者名：Okabe, A., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition46(1),177-188
  2000年03月, 共同
• 土壌中のガンマプロテオバクテリア
  『新・土の微生物（５）系統分類から見た土の細菌』pp.139-152 博友社
  2000年03月, 単独
• 土壌中の高G+Cグラム陰性細菌
  著者名：岡村幸治・豊田剛己
  『新・土の微生物（５）系統分類から見た土の細菌』pp.82-101 博友社
  2000年03月, 共同
• Phenotypic characterization of a mutant of Burkholderia cepacia MRT11 defective in rhizosphere competence
  著者名：Toyota, K., Hiraiwa (Nojiri), C. and Kimura, M.
  Microbes and Environments14(4), 201-208
  1999年12月, 共同
• Effect of soil temperature and anaerobiosis on degradation of biodegradable plastics in soil and their degrading microorganisms
  著者名：Nishide, H., Toyota, K. and Kimura, M
  Soil Science and Plant Nutrition45(4), 963-972
  1999年12月, 共同
• Epibiotic microorganisms associated with microcrustaceans in overlying water of Philippine paddy fields
  著者名：Taniguchi, T., Ventura, W., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition45(3), 757-766
  1999年09月, 共同
• Impact of fumigation with metam sodium upon soil microbial　 community structure in two Japanese soils
  著者名：Toyota, K., Ritz, K., Kuninaga, S. and Kimura, M.
  Soil Science and Plant Nutrition45(1), 207-223
  1999年03月, 共同
• 蛍光性Pseudomonadsの根面定着因子に関する生態学的アプローチ
  著者名：豊田剛己・池田恭子・木村眞人
  土と微生物52、53-63
  1998年10月, 共同
• 植物と微生物
  著者名：豊田剛己・木村眞人
  『バイオフィルム』サイエンスフォーラムp.125-139
  1998年10月, 共同
• 土壌病害とバイオテクノロジー
  著者名：豊田剛己・木村眞人
  『土と食糧?健康な未来のために』朝倉書店、p. 61-63
  1998年09月, 共同
• Effects of bacterial colonization of tomato roots on subsequent colonization by Pseudomonas fluorescens MelRC2Rif
  著者名：Ikeda, K., Toyota, K. and Kimura, M.
  Canadian Journal of Microbiology44(7), 630-636
  1998年05月, 共同
• Role of extracellular pectinases in the rhizoplane competence of a rhizobacterium Burkholderia pickettii MSP3rif
  著者名：Ikeda, K., Toyota, K. and Kimura, M.
  Soil Biology and Biochemistry30(3), 323-329
  1998年03月, 共同
• 連作障害と土壌環境
  著者名：豊田剛己・木村眞人
  農業及び園芸73(1)、151-157
  1998年01月, 共同
• Relative importance of motility and antibiotics in the rhizoplane competence of a biocontrol agent Pseudomonas fluorescens MelRC2Rif
  著者名：Toyota, K. and Ikeda, K.
  Biology and Fertility of Soils25, 416-420
  1997年11月, 共同
• 植物の根と微生物
  著者名：木村眞人・豊田剛己
  『新・土の微生物（２）植物の生育と微生物』博友社、p. 5-40
  1997年10月, 共同
• Seasonal variation of microcrustaceans and microbial flora on their surfaces in the overlying water in a Japanese paddy field
  著者名：Taniguchi, M., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition43(3), 651-664
  1997年09月, 共同
• Epibiotic bacterial flora on microcrustaceans in the overlying water of rice paddies
  著者名：Taniguchi, M., Toyota, K. and Kimura, M.
  Soil Science and Plant Nutrition43(3), 633-641
  1997年09月, 共同
• Effects of soil compaction on the microbial populations of melon and maize rhizoplane
  著者名：Ikeda, K., Toyota, K. and Kimura, M.
  Plant and Soil189, 91-96
  1997年02月, 共同
• Growth of the bacterial wilt pathogen Pseudomonas solanacearum introduced into soil colonized by individual soil bacteria
  著者名：Toyota K. and Kimura M.
  Soil Biology and Biochemistry28(10/11), 1489-1494
  1996年10月, 共同
• Microbiological factors affecting the colonization of soil aggregates by Fusarium oxysporum f. sp. raphani
  著者名：Toyota, K., Ritz, K. and Young, I. M.
  Soil Biology and Biochemistry28(10/11), 1513-1521
  1996年10月, 共同
• Survival of bacterial and fungal populations following chloroform- fumigation: The effect of soil matric potential adn bulk density
  著者名：Toyota, K., Ritz, K. and Young, I. M.
  Soil Biology and Biochemistry28(10/11), 1545-1547
  1996年10月, 共同
• Effects of soil matric potential and bulk density on the growth of Fusarium oxysporum f. sp. raphani
  著者名：Toyota, K., Young, I. M. and Ritz, K
  Soil Biology and Biochemistry28(9), 1139-1145
  1996年09月, 共同
• ダイコン萎黄病菌の生態研究の現状と展望
  著者名：豊田剛己・木村眞人
  植物防疫50(10)、411-416
  1996年02月, 共同
• Mechanisms of biodegradation of lignite piled in the open air
  著者名：Yuan, H. L., Toyota, K. and Kimura, M
  Bull. Japanese Society of Microbial Ecology10(2), 53-58
  1995年06月, 共同
• Observation with scanning electron　 microscope of microbial succession　 on lignite along with weathering
  著者名：Yuan, H. L., Toyota, K. and Kimura, M.
  Bull. Japanese Society of Microbial Ecology10(2), 59-65
  1995年06月, 共同
• Autecology of Fusarium oxysporum f. sp. raphani in soils suppressive and conducive to Fusarium-wilt of radish
  著者名：Toyota, K., Kjamesaka, T.. and Kimura, M.
  FEMS Microbiology Ecology16(4), 261-268
  1995年04月, 共同
• クリスタルバオレット耐性による土壌中のグラム陰性菌数推定の妥当性
  著者名：豊田剛己・木村眞人
  土と微生物45, 3-7
  1995年03月, 共同
• Suppression of Fusarium oxysporum f. sp. raphani PEG-4 in soil following colonization by other Fusarium spp.
  著者名：Toyota, K., Kitamura, M. and Kimura, M.
  Soil Biology and Biochemistry27(1), 41-46
  1995年01月, 共同
• Changes of chemical properties and microbial succession of lignites with weathering
  著者名：Yuan, H. L., Toyota, K., Watanabe, A. and Kimura, M.
  Bull Japanese Society of Microbial Ecology9(2), 45-53
  1994年12月, 共同
• Isolation and characterization of　 bacteria responsible for the suppression of Fusarium oxysporum f. sp. raphani on the host rhizoplane
  著者名：Toyota, K., Yamamoto, K. and Kimura, M.
  Soil Science and Plant Nutrition40(3), 381-390
  1994年09月, 共同
• Mechanisms of suppression of in Fusarium oxysporum f. sp. raphani soils so-called suppressive to Fusarium-wilt of radish
  著者名：Toyota, K., Yamamoto, K. and Kimura, M.
  Soil Science and Plant Nutrition40(3), 373-380
  1994年09月, 共同
• Earthworms disseminate a soil- borne plant pathogen, Fusarium　 oxysporum f. sp. raphani
  著者名：Toyota K. and Kimura M.
  Biology and Fertility of Soils18(1), 32-36
  1994年06月, 共同
• 有機物の土壌病害抑制効果?ダイコン萎黄病菌に対する有機物の施用効果?
  著者名：豊田剛己・木村眞人
  『農業技術体系土壌施肥編５土壌管理・土壌病害（追録）』 農山漁村文化協会 追録第5号、第5巻、畑98の2ｰ12
  1994年06月, 共同
• Introduction of a chitinase gene into Pseudomonas stutzeri A18 isolated from the surface of chlamydospores of Fusarium oxysporum f. sp. raphani
  著者名：Toyota, K., Miyashita, K. and Kimura, M.
  Soil Biology and Biochemistry26(3), 413-416
  1994年03月, 共同
• Fusarium oxysporum f. sp. raphani厚膜胞子付着菌の他の病原性フザリウム菌に対する付着能及び拮抗能
  著者名：豊田剛己・木村眞人
  土と微生物43, 1-8
  1994年03月, 共同
• Effects of soil conditions on biodegradation of plastics and responsible microorganisms
  著者名：Kimura, M., Toyota, K., Iwatsuki, M. and Sawada, H.
  『Biodegradable Plastics Polymersand』Elsevier Sciences Co.p. 92-106
  1994年, 共同
• Colonization of chlamydospores of Fusarium oxysporum f. sp. raphani by soil bacteria and their effects on germination
  著者名：Toyota, K. and Kimura M.
  Soil Biology and Biochemistry25(2), 193-197
  1993年02月, 共同
• Population dynamics of Fusarium oxysporum f. sp. raphani in soils of different fungistatic capacity
  著者名：Toyota, K. and Kimura M.
  FEMS Microbiology Ecology102(1), 15-20
  1992年12月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani)の生態（第７報）日本各地より採取したダイコン萎黄病菌の土壌中における発芽及び発芽管伸長
  著者名：豊田剛己・木村眞人
  日本土壌肥料学会誌63(6), 703-704
  1992年12月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani)の生態（第６報）ダイコン根圏におけるダイコン萎黄病菌の生育
  著者名：豊田剛己・木村眞人
  日本土壌肥料学会誌63(5), 566-570
  1992年10月, 共同
• Potential application of genetic transformants of Fusarium oxysporum f. sp. raphani for assessing fungal autecology
  著者名：Toyota, K., Tsuge, T. and Kimura, M.
  Soil Biology and Biochemistry24(5), 489-494
  1992年05月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani) の生態（第５報）ダイコン萎黄病菌の厚膜胞子に付着する微生物
  著者名：豊田剛己・木村眞人
  日本土壌肥料学会誌62(5), 533-535
  1991年10月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani) の生態（第４報）土壌中のFusarium oxysporum f. sp. raphani菌糸・胞子の生育に及ぼすすきゅう肥施用効果
  著者名：豊田剛己・木村眞人
  日本土壌肥料学会誌62(2), 122-127
  1991年04月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani）の生態（第３報）土壌中のFusarium oxysporum f. sp. raphani に対する拮抗菌
  著者名：豊田剛己・木村眞人
  日本土壌肥料学会誌62(1), 21-26
  1991年02月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp. raphani）の生態（第２報）厩肥連用土壌のFusarium oxysporum f. sp. raphani 抑制機構
  著者名：木村眞人・豊田剛己・鍬塚昭三
  日本土壌肥料学会誌62(1), 13-20
  1991年02月, 共同
• 土壌中におけるダイコン萎黄病菌（Fusarium oxysporum f. sp.　raphani）の生態（第１報）化学肥料および厩肥連用土壌におけるFusarium oxysporum f. sp. raphaniの生育
  著者名：木村真人・豊田剛己・鍬塚昭三
  日本土壌肥料学雑誌61(6), 586-591
  1990年12月, 共同

著書

• 植物病原微生物の種類と制御
  豊田剛己
  豊田剛己編 実践土壌学シリーズ１．土壌微生物学
  2018年08月
• 生物資源の宝庫（生物性の利用）
  豊田剛己
  木村眞人・南條正巳編「土壌サイエンス入門第二版」
  2017年08月
• 土壌に窒素が供給されると大気中の二酸化炭素が減少する？
  沢田こずえ・豊田剛己
  日本土壌肥料学会「土のひみつ」編集グループ編「土のひみつ」
  2015年09月
• 土の生物
  豊田剛己
  日本土壌肥料学会「土のひみつ」編集グループ編「土のひみつ」
  2015年09月
• 日本微生物生態学会編「環境と微生物の事典」微生物の住処としての土壌、カビ、植物の生育を妨げる微生物,
  豊田剛己
  朝倉書店
  2014年07月
• シリーズ21世紀の農学　農林水産業を支える生物多様性の評価と課題、農耕地土壌における微生物多様性の評価手法とその利用
  豊田剛己
  養賢堂
  2011年04月
• 図説日本の土壌
  岡崎正規・木村園子ドロテア・波多野隆介・豊田剛己・林健太郎
  朝倉書店
  2010年04月
• 畑地生態系の生物性評価手法の開発に向けた試みー線虫群集と線虫害ー。日本土壌肥料学会編「土壌の原生生物・線虫群集ーその土壌生態系での役割ー」
  豊田剛己・佐藤恵利華
  博友社
  2009年09月, 978-4-8268-0212-3
• 繰り返し栽培による土壌病害の生物防除、百町満朗・対馬誠也編微生物と植物の相互作用-病害と生物防除-
  豊田剛己
  ソフトサイエンス社
  2009年03月
• 糖、アミノ酸の添加による青枯病抑制、百町満朗・対馬誠也編微生物と植物の相互作用-病害と生物防除-
  豊田剛己
  ソフトサイエンス社
  2009年03月
• 植物の病気を防ぐ.生物に学び新しいシステムを創る編集委員会編、生物に学び新しいシステムを創る
  豊田剛己
  博友社
  2006年04月
• 農薬の行方と安全性、村橋俊一・御園生誠編、役にたつ化学シリーズ⑨　地球環境の化学、
  豊田剛己
  朝倉書店
  2006年02月
• 食料生産と農薬、村橋俊一・御園生誠編、役にたつ化学シリーズ⑨　地球環境の化学、
  豊田剛己
  朝倉書店
  2006年02月
• 部分殺菌効果からバイオマス研究へ
  土壌微生物研究会編
  博友社
  2003年05月

研究発表、招待講演等

• Residue Analysis of Chlorpyrifos in Broccoli using HPLC
  農薬残留分析研究会
  2019年10月31日, ポスター発表
• 武田 藍・福田 寛・豊田 剛己
  日本線虫学会
  2019年09月11日, 口頭発表（一般）
• 連作障害の原因となる土壌伝染性病原菌・線虫の生態、診断、防除に関する研究
  日本土壌肥料学会
  2019年09月04日, 口頭発表（招待・特別）
• ダイズシストセンチュウの生態的特徴と防除対策
  平成30年度丹波篠山黒豆栽培研修会
  2019年03月14日, 公開講演，セミナー，チュートリアル，講習，講義等
• 緑肥Crotalaria junceaによるモロコシネグサレセンチュウ(Pratylenchus zeae)の増加抑制
  日本土壌肥料学会関東支部会
  2018年12月01日, ポスター発表
• 土壌病害、センチュウ害診断・対策の動向
  土壌医の会全国交流大会
  2018年11月30日, 公開講演，セミナー，チュートリアル，講習，講義等
• ダイズシストセンチュウ密度測定の精緻化
  日本線虫学会
  2018年09月05日, ポスター発表
• リアルタイムPCR を用いたミャンマーゴマ圃場におけるHeterodera cajani の生息状況の調査と緑肥を使った生物学的防除の開発
  日本線虫学会
  2018年09月05日, ポスター発表
• 緑豆すき込みによるダイズシストセンチュウへの影響～水分と孵化の関係～
  日本線虫学会
  2018年09月05日, ポスター発表
• 土壌診断における土壌生物性分析の重要性
  第7回土壌診断分析研究会
  2018年07月10日, 口頭発表（招待・特別）
• 「枝豆のダイズシストセンチュウ総合防除について」～埼葛地域の調査結果から～
  JAさいかつ主催セミナー
  2018年07月03日, 公開講演，セミナー，チュートリアル，講習，講義等
• 「枝豆のダイズシストセンチュウ総合防除について」～埼玉県での調査事例も含めて～
  枝豆センチュウ対策研修会
  2018年03月14日, 公開講演，セミナー，チュートリアル，講習，講義等
• ミャンマーのゴマ圃場におけるHeterodera cajaniによる汚染状況の把握と生物学的防除
  日本土壌肥料学会関東支部会
  2017年11月25日, ポスター発表
• 緑豆すき込みによるダイズシストセンチュウ防除法の開発 温度・土壌水分の影響（室内試験）
  日本土壌肥料学会関東支部会
  2017年11月25日, ポスター発表
• 武田 藍・豊田剛己
  日本線虫学会
  2017年09月22日, 口頭発表（一般）
• 有機物連用土壌と微生物の働き
  NGK・GGG共同主催　平成28年度「ゴルフ場環境セミナー」
  2017年03月02日, 公開講演，セミナー，チュートリアル，講習，講義等
• 「枝豆のダイズシストセンチュウ総合防除について」～埼玉県での調査事例も含めて～
  えだまめのダイズシストセンチュウ防除対策研修会
  2017年02月20日, 公開講演，セミナー，チュートリアル，講習，講義等
• Stable Isotope Probingによるベンゼン、トルエン、ジクロロメタン複合汚染分解微生物の同定
  日本微生物生態学会
  2016年10月23日, その他
• ニンニク腐敗の原因線虫イモグサレセンチュウの要防除水準確立に向けた基礎研究
  日本線虫学会
  2016年09月15日, その他
• 沖縄キク圃場におけるネグサレセンチュウの分布状況
  日本線虫学会
  2016年09月15日, その他
• Effects of dry biogas digestate application on root knot nematodes and soybean cyst nematodes
  日本線虫学会
  2016年09月14日, その他
• 2種の土壌くん蒸剤が土壌病害虫および一般微生物に与える影響の比較
  日本土壌微生物学会
  2016年06月11日, ポスター発表
• Development of real-time PCR primers for the quantification of Heterodera cajani and its control in Myanmar
  Advances in Nematology
  2015年12月, その他
• 複合汚染の微生物分解におけるジクロロメタン、ベンゼン及びトルエンの相互作用
  日本微生物生態学会
  2015年11月24日, ポスター発表
• 糖蜜施用がサトウキビ収量・品質、土壌化学性に及ぼす影響
  日本土壌肥料学会
  2015年09月09日, ポスター発表
• メタン発酵残渣を用いた土壌病害の抑制効果
  日本土壌肥料学会
  2015年09月09日, ポスター発表
• Real-time PCR法を用いたニンニク腐敗の原因線虫イモグサレセンチュウの診断技術の確立
  日本線虫学会
  2015年09月04日, その他
• ミャンマー中部に分布する植物寄生性線虫の同定と定量
  日本線虫学会
  2015年09月04日, その他
• 首都圏のエダマメ圃場におけるダイズシストセンチュウの発生状況および緑肥による防除
  日本線虫学会
  2015年09月04日, その他
• 糖蜜施用がサトウキビ収量・品質、土壌化学性に及ぼす影響
  第42回サトウキビ試験成績発表会
  2015年08月18日, その他
• 北大東島におけるサトウキビ収量と植物寄生性線虫の関係について
  第42回サトウキビ試験成績発表会
  2015年08月18日, その他
• ジクロロメタンを含む複合汚染の好気的微生物分解機構
  第21回地下水・土壌汚染研究集会
  2015年06月19日, ポスター発表
• 土壌病害と有機物施用
  日本土壌微生物学会　つくば大会シンポジウム
  2015年05月22日, 口頭発表（招待・特別）
• 徳島県東北部の砂地畑におけるサツマイモネコブセンチュウ Meloidogyne incognitaに対する殺線虫剤の影響について
  日本応用動物昆虫学会
  2015年03月17日, その他
• 食糧問題解決の一助となる土壌病害対策とその診断
  日本農芸化学会産学官若手交流会　第２３回ワークショップ
  2015年01月28日, 口頭発表（招待・特別）
• 殺線虫剤（カズサホス, ホスチアゼート）の繰り返し使用と微生物分解促進による不効化現象の関係
  環境微生物系学会合同大会
  2014年10月22日, ポスター発表
• 塩害土壌におけるファイトレメディエーションに植物生育促進細菌を接種した影響
  環境微生物系学会合同大会
  2014年10月22日, ポスター発表
• 有機栽培・減農薬栽培土壌のキュウリ苗立枯病およびダイコン苗立枯病の発病抑制
  環境微生物系学会合同大会
  2014年10月22日, ポスター発表
• Isolation of spore-forming bacteria from a Fusarium wilt-suppressive soil and their utilization against the major tomato soil-borne pathogens
  環境微生物系学会合同大会
  2014年10月22日, ポスター発表
• Development of a generic real-time PCR approach of plant-parasitic nematodes in Okinawa using benchmark nematodes
  日本線虫学会
  2014年09月17日, その他
• 埼玉県枝豆圃場におけるリアルタイムPCR法を用いた　ダイズシストセンチュウの要防除水準の作成
  日本線虫学会
  2014年09月17日, ポスター発表
• Effect of whole crop rice cultivars and biogas slurry application on methane emission in a paddy field in Japan
  日本土壌肥料学会
  2014年09月10日, ポスター発表
• 北大東島サトウキビ圃場における植物寄生性線虫とサトウキビ初期生育の関係、 および対抗植物としての緑肥に関する研究
  第41回サトウキビ試験成績発表会
  2014年08月20日, その他
• 堆肥をはじめとする各種有機質肥料による土壌機能の向上
  肥料科学研究所平成26年度第1回研究会
  2014年07月15日, 口頭発表（招待・特別）
• リアルタイムＰＣＲ法を用いたネコブセンチュウの迅速評価
  日本植物病理学会
  2014年06月04日, その他
• Identification of pathogens causing root rot of lotus and development of specific primers to them.
  18th Biological Sciences Graduate Congress
  2014年01月06日, ポスター発表
• 化学農薬の使用量低減を目指した 新規センチュウ診断
  アグリビジネス創出フェア2013
  2013年10月24日, 口頭発表（招待・特別）
• Effect of biogas slurry application on CH4 and N2O emissions, Cu and Zn uptakes by whole crop rice in a paddy field in Japan
  日本土壌肥料学会
  2013年09月11日, ポスター発表
• 異なるメタン発酵残渣を水田に投入した際の環境負荷
  日本土壌肥料学会
  2013年09月11日, ポスター発表
• 北大東島サトウキビ圃場における植物寄生性線虫と薬剤の殺線虫効果に関する研究
  第40回サトウキビ試験成績発表会
  2013年08月27日, その他
• フザリウム属菌およびピシウム属菌によるレンコン腐敗病菌の密度と収量の関係
  日本土壌微生物学会
  2013年06月20日, ポスター発表
• メタン発酵残渣の土壌病害に及ぼす影響
  日本土壌微生物学会
  2013年06月20日, ポスター発表
• A nematode diagnostic method using the direct quantification of root knot nematodes in soil and its economical threshold to carrot
  The 13th International Symposium for Environmental issues in Korea and Japan
  2012年12月08日, その他
• Environmental impact in the application of different anaerobic digested slurries to paddy field
  The 13th International Symposium for Environmental issues in Korea and Japan
  2012年12月08日, その他
• Development of the real-time PCR primers specific to sugarcane plant-parasitic nematodes, Helicotylenchus dihystera, Pratylenchus zeae and Tylenchorhynchus leviterrminalis, in Minami-daito island.
  日本線虫学会
  2012年09月20日, その他
• 徳島県レンコン圃場におけるリアルタイムPCR法を用いたレンコンネモグリセンチュウの要防除水準の作成
  日本線虫学会
  2012年09月20日, その他
• リアルタイムPCR法を用いたキタネコブセンチュウ定量のための検量線作成の試み
  日本線虫学会
  2012年09月20日, その他
• リアルタイムPCR による 線虫密度診断技術
  日本線虫学会20 周年記念シンポジウム
  2012年09月19日, 口頭発表（招待・特別）
• 野外土壌中におけるもやし残渣をもちいたダイズシストセンチュウの防除
  日本土壌微生物学会
  2011年11月25日, その他
• 有機栽培圃場におけるキタネグサレセンチュウ被害抑止土壌のメカニズム解析
  日本土壌微生物学会
  2011年11月25日, その他
• 土壌生物性と土壌病虫害との関連 ―土壌生物性診断は発病リスクを評価できるか ―
  平成23年度農研機構セミナー野菜の土壌病虫害防除における環境保全的対策研究の最前線 － 病原菌の識別・定量検出、発病リスクの評価、防除技術について－
  2011年10月20日, 口頭発表（招待・特別）
• Development of specific primers to root rot nematodes Hirschmanniella spp. causing damage to lotus and relationship between the initial density and the damage index.
  日本線虫学会
  2011年09月11日, その他
• 愛知県木曽川流域におけるダイコンのリアルタイムPCR法を用いたキタネグサレセンチュウ要防除水準の作成
  日本線虫学会
  2011年09月11日, その他
• 微生物の各種機能から見た土壌の働き－物質循環と病害の二面性－
  日本土壌肥料学会2011年度大会（つくば大会）第6部門シンポジウム
  2011年09月10日, 口頭発表（招待・特別）
• 農耕地土壌における微生物多様性の評価手法とその利用
  2010年度日本農学会シンポジウム 「農林水産業を支える生物多様性の評価と課題」
  2010年10月08日, 口頭発表（招待・特別）
• Development of a novel diagnostic method for nematode diseases
  The 11th International Symposium for Environmental issues in Korea and Japan
  2010年08月11日, その他
• 農薬による土壌微生物の活動制御
  日本農薬学会シンポジウム「クリーン農業に果たす農薬・薬剤の役割」
  2010年05月30日, 口頭発表（招待・特別）
• Greenhouse gas emissions in paddy fields fertilized with anaerobically digested cattle slurry and approach to their mitigation
  Japan-China Joit Symposium on Purification of Livestock Wastewater and Bioremediation of Water Environment basing on Strengthened Biological Function
  2010年02月22日, その他
• Novel detection method for plant parasitic nematodes and its application into suppression mechanism to root-lesion nematode in a soil amend with okara and coffee compost
  Annual Meeting, British Socity of Soil Science and Soil Science Society of Ireland
  2009年09月11日, ポスター発表
• Enhancement of soil functional stability by organic amendment and possible contribution of aggregated soil structure
  Eusosoil 2008
  2008年08月26日, ポスター発表
• Quantitative detection of the major plant-parasitic nematodes in Japan using real-time PCR
  International Congress of Nematology
  2008年07月17日, ポスター発表
• Possible mechanisms decreasing the damage on radish by the root-lesion nematode in a soil amended with okara and coffee compost
  International Congress of Nematology
  2008年07月17日, 口頭発表（招待・特別）
• Microbiological factors affecting nitrous oxide emission from an agricultural peat soil in Kalimantan.soils
  JSPS-LIPI Core University Program: International Symposium on Nature and Land Management of Tropical Peat land in South East Asia
  2006年09月20日, その他
• N2O emission and soil microbial community structure following organic matter amendment in herbicide treated soils
  JSPS-LIPI Core University Program: International Symposium on Nature and Land Management of Tropical Peat land in South East Asia
  2006年09月20日, その他
• Suppression of Soil Borne Pathogens by Biocontrol Agents Isolated from Kalimantan Soil.
  JSPS-LIPI Core University Program: International Symposium on Nature and Land Management of Tropical Peat land in South East Asia
  2006年09月20日, その他
• POR-DGGEとqPCRによる線虫群集および有害線虫数の推計に向けた取り組み
  日本線虫学会
  2006年09月14日, その他
• 定量PCRによるPratylenchus penetransの検出。
  日本線虫学会
  2006年09月14日, その他
• レタス・ホウレンソウの糸状菌病害に対するメタン消化液の施用効果
  日本土壌肥料学会
  2006年09月05日, その他
• N2O emission and soil microbial community structure following organic matter amendment in herbicide treated soils
  日本土壌肥料学会
  2006年09月05日, その他
• 土壌の凍結融解が脱窒能に及ぼす影響：第2報－アセチレン阻害法で得られる亜酸化窒素生成曲線の解析
  日本土壌肥料学会
  2006年09月05日, その他
• Stimulation of N2O production and reduction in soil under frozen condition.
  Asian Conference on Permafrost.
  2006年08月, ポスター発表
• itrogen-fixing ability of Sterilized and Non-sterilized Sago root and Starch and Isolation of Nitrogen-fixing Bacteria from them
  1st Philippine Sago Symposium "Unraveling Sago's Potentials
  2006年07月28日, その他
• Suppressive mechanisms of used pumice to bacterial wilt of tomato and biological control in hydroponic pumice culture
  International Symposium of Bacterial Wilt
  2006年07月18日, その他
• トマト青枯病菌を接種した軽石培地およびトマト根の細菌群集構造の経時的変化。
  日本土壌微生物学会
  2006年07月10日, その他
• 拮抗菌と糖、アミノ酸の併用による効果的なトマト青枯病防除
  日本土壌微生物学会
  2006年07月10日, ポスター発表
• Selection of Biocontrol Agents for Bacterial Wilt of Tomato from Kalimantan Soils
  Annual meeting of the Japanese Society of Soil Microbiology
  2006年07月10日, ポスター発表

外部研究資金等

• 都市近郊エダマメ栽培体系に適応したダイズシストセンチュウの生物的防除法の開発
  受託研究, 自 2016年04月18日, 至 2017年03月31日
• 線虫防除機能を有する革新的緑肥技術の開発によるサトウキビの連作障害回避と増産
  受託研究, 自 2016年04月18日, 至 2017年03月31日
• イモグサレセンチュウの定量的検出法の開発
  共同研究, 自 2016年04月18日, 至 2017年02月28日
• 土壌環境診断
  受託研究, 自 2016年04月01日, 至 2017年03月31日
• 植物寄生性線虫病害の総合的診断
  受託研究, 自 2016年02月26日, 至 2016年04月30日
• ダイズシストセンチュウのReal-time PCR　分析一式
  受託研究, 自 2015年09月01日, 至 2016年03月31日
• 植物寄生性線虫病害の総合的診断
  受託研究, 自 2015年09月01日, 至 2015年12月31日
• 農業向け集積化センサの研究
  共同研究, 自 2015年05月11日, 至 2016年05月10日
• イモグサレセンチュウの定量的検出法の開発
  共同研究, 自 2015年04月06日, 至 2016年02月29日
• 土壌消毒剤が土壌微生物に及ぼす環境調査
  受託研究, 自 2015年04月01日, 至 2016年03月31日
• ナノ粒子選択型植物育成装置『ミストプランター』の試作開発
  受託研究, 自 2015年04月01日, 至 2015年06月15日
• ナノ粒子選択型植物育成装置『ミストプランター』の試作開発
  受託研究, 自 2014年12月15日, 至 2015年03月31日
• アグロカネショウ
  受託研究, 自 2014年10月01日, 至 2015年03月31日
• 植物寄生性線虫病害の総合的診断
  受託研究, 自 2014年09月01日, 至 2014年12月20日
• 農業産業化ジャパンクオリティ・システム形成に向けた革新的生産技術体系の確立
  受託研究, 自 2014年04月18日, 至 2015年03月06日
• 土壌中に生息する植物寄生性線虫、病害菌の分析
  受託研究, 自 2014年04月01日, 至 2015年03月31日
• ほうれんそう畑土壌に発生する萎凋病菌の分析手法の開発
  受託研究, 自 2014年04月01日, 至 2015年03月31日
• ながいも畑土壌に発生する根腐れ病菌の分析手法の開発
  受託研究, 自 2014年04月01日, 至 2015年03月31日
• いちご培土等に生息する線虫の分析手法の開発
  受託研究, 自 2014年04月01日, 至 2015年03月31日
• 土壌からの土壌線虫及び土壌病原菌類DNAの抽出方法の習得と、リアルタイムPCRを使用した定量方法の習得
  受託研究, 自 2014年03月20日, 至 2014年03月31日
• ＩＴ融合による新社会システムの開発・実証プロジェクト/（農商工連携分野）農業産業化ジャパンクオリティ・システム形成に向けたスマートＳＣＭ融合基盤の開発/土壌分析及び計測機器との相関性分析業務
  受託研究, 自 2013年04月01日, 至 2014年03月31日
• 太陽熱消毒と温湯処理を核とした省力的なレンコン土壌病害虫防除体系の確立
  受託研究, 自 2013年04月01日, 至 2014年03月05日
• ＩＴ融合による新社会システムの開発・実証プロジェクト（農商工連携分野）農業産業化ジャパンクオリティ・システム形成に向けたスマートＳＣＭ融合基盤の開発　土壌分析及び計測機器との相関性分析業務
  受託研究, 自 2012年12月03日, 至 2013年03月31日
• 太陽熱消毒と温湯処理を核とした省力的なレンコン土壌病害虫防除体系の確立
  受託研究, 自 2012年04月06日, 至 2013年03月01日
• 太陽熱消毒と温湯処理を核とした省力的なレンコン土壌病害虫防除体系の確立
  受託研究, 自 2011年06月30日, 至 2012年03月09日
• メタゲノム線虫診断の導入による殺線虫剤使用量の30%削減
  受託研究, 自 2011年04月01日, 至 2012年03月22日
• 「太陽熱消毒法を核としたれんこんの土壌病虫害対策による産地強化」のうち 土壌病害虫簡易検定法の検討
  受託研究, 自 2010年06月28日, 至 2011年03月18日
• レタスの共生微生物に関する研究
  共同研究, 自 2010年06月01日, 至 2011年03月31日
• メタゲノム線虫診断の導入による殺線虫剤使用量の30%削減
  受託研究, 自 2010年04月01日, 至 2011年03月12日
• 土壌病害発生・抑止要因としての土壌生物相の解析
  受託研究, 自 2010年04月01日, 至 2011年03月01日
• メタゲノム線虫診断の導入による殺線虫剤使用量の30%削減
  受託研究, 自 2009年06月30日, 至 2010年03月19日
• 畑への殺線虫剤の使用要否を判断する線虫診断技術の開発
  受託研究, 自 2009年06月17日, 至 2010年03月31日
• 土壌病害発生・抑止要因としての土壌生物相の解析
  受託研究, 自 2009年04月01日, 至 2010年03月12日
• 土壌病害発生・抑止要因としての土壌生物相の解析
  受託研究, 自 2008年05月01日, 至 2009年03月05日
• トマト青枯病抑制土壌のメカニズムの解明に関する研究
  共同研究, 自 2007年06月01日, 至 2008年03月31日
• 土壌病害発生・抑止要因としての土壌生物相の解析
  受託研究, 自 2007年06月01日, 至 2008年03月06日
• 平成1９年度先端技術を活用した農林水産研究高度化事業委託事業
  受託研究, 自 2007年05月25日, 至 2008年03月19日
• 環境負荷低減型高機能養液栽培システムの開発
  受託研究, 自 2006年06月29日, 至 2007年03月16日
• 土壌病害発生・抑止要因としての土壌生物相の解析
  受託研究, 自 2006年06月09日, 至 2007年03月06日
• トマト根圏微生物群集の多様性に基づく病害抑制評価手法の開発
  共同研究, 自 2006年02月01日, 至 2006年12月31日
• トマト青枯病を抑制する有機物施用条件とその機構解明
  受託研究, 自 2005年08月05日, 至 2006年02月28日
• 平成17年度先端技術を活用した農林水産研究高度化事業委託事業
  受託研究, 自 2005年07月12日, 至 2006年03月18日
• ①連作障害抑制機構の解明　②メタン発酵消化液の農業利用
  共同研究, 自 2004年12月01日, 至 2006年05月31日
• トマトの青枯病を抑制する有機物質施用条件とその機構の解明
  受託研究, 自 2004年06月28日, 至 2005年02月28日

委員歴

• 日本土壌肥料学会
  部門長
  自 201510, 至 201809
• 日本土壌肥料学会
  欧文誌編集委員
  自 201310, 至 201709
• 日本土壌微生物学会「土と微生物」
  編集委員長
  自 200801, 至 201312
• Microbes and Environments
  Editor
  自 2007, 至 0000
• Microbes and Environments
  Senior Editor
  自 2007, 至 201001
• サゴヤシ学会
  編集委員長
  自 2004, 至 0000
• 日本土壌微生物学会
  会計幹事
  自 200401, 至 200712
• サゴヤシ学会
  会計幹事
  自 2001, 至 0000
• 日本土壌微生物学会
  評議員
  自 2001, 至 0000
• 日本土壌肥料学会
  副部門長
  自 2000, 至 2002

メディア報道

• センチュウ買いを減らす！シマニチ科研「シーマロックス液肥土壌潅水によるセンチュウ抑制効果について」
  シマニチ科研は、シーマロックス液肥によるセンチュウの抑制効果が判明したことを発表した。実験は農工大 豊田研究室に依頼、行ったと紹介される。
  Dtimes
  自 2023年10月09日, 至 2023年10月09日
• 担い手　注目集まるが課題も　バイオスティミュラントとは
  土壌微生物を研究する東京農工大学の豊田剛己教授の指摘が紹介される。
  日本農業新聞
  自 2022年10月17日, 至 2022年10月17日
• 線虫密度７割削減
  東京農工大学の豊田剛己教授らは、枝豆のダイズシストセンチュウの対策で、緑豆のすき込みによる防除技術を確立したことが紹介される。
  日本農業新聞
  自 2021年05月13日, 至 2021年05月13日
• 土壌の化学性　手合せ分析７月、東京で研究会
  研究会で、本学大学院の豊田剛己教授が特別講演する予定であることが紹介される。
  日本農業新聞
  自 2018年05月09日, 至 2018年05月09日

所属学協会

• 日本土壌肥料学会
  自 2015年10月, 至 2018年09月
• 日本土壌肥料学会
  自 2013年10月, 至 2017年09月
• 日本土壌微生物学会「土と微生物」
  自 2008年01月, 至 2013年12月
• Microbes and Environments
  自 2007年
• Microbes and Environments
  自 2007年, 至 2010年01月
• 日本土壌微生物学会
  自 2004年01月, 至 2007年12月
• サゴヤシ学会
  自 2004年
• サゴヤシ学会
  自 2001年
• 日本土壌微生物学会
  自 2001年
• 日本土壌肥料学会
  自 2000年, 至 2002年
• 日本線虫学会
• 日本土壌動物学会
• 日本微生物生態学会

受賞

• 日本土壌肥料学会
  日本土壌肥料学会賞
  2019年04月19日
• 日本土壌肥料学会奨励賞
  2003年
• 井上研究奨励賞
  1994年
• British Council Fellowship
  1994年