Hayashi Kana Y, Nagamatsu Yukiko, Kawano Moemi, Fuchimoto Sayaka, Araki Tsuyoshi, Saito Tamao
Graduate School of Science and Technology, Sophia University, Chiyoda-ku, Tokyo 102-8554, Japan.
Environmental Science Research Institute, Panefri Industrial Co., Ltd., Naha, Okinawa 903-0815, Japan.
J Agric Food Chem. 2025 Aug 6;73(31):19315-19326. doi: 10.1021/acs.jafc.5c04345. Epub 2025 Jul 29.
Root-knot nematodes are major pests of various crops, coexisting in the soil with amoebae, such as the cellular slime mold . Prior studies have indicated that nematodes prey on prompting investigations into whether amoebae possess chemical defenses against nematodes for potential use in crop protection. Using improved culture and extraction methods, we found that releases metabolites acting as repellents against root-knot nematodes, including L-type basic amino acids (e.g., l-histidine, l-arginine) and antioxidants (e.g., l-ascorbic acid, l-cysteine). A mixture of 14 different repellents proved to be extremely potent. The crude conditioned medium that facilitated the identification of these repellents inhibited root-knot nematode egg hatching, exhibited nematocidal effects, and promoted plant growth in pot tests. These findings suggest that the identified compounds and conditioned medium could provide a novel method for nematode control applicable to crops that lack existing control measures.
根结线虫是多种作物的主要害虫，与变形虫（如细胞黏菌）共存于土壤中。先前的研究表明线虫会捕食，这促使人们研究变形虫是否具有针对线虫的化学防御机制，以便在作物保护中加以利用。通过改进培养和提取方法，我们发现会释放对线结线虫起驱避作用的代谢物，包括L型碱性氨基酸（如L-组氨酸、L-精氨酸）和抗氧化剂（如L-抗坏血酸、L-半胱氨酸）。14种不同驱避剂的混合物被证明具有极强的效力。有助于鉴定这些驱避剂的粗制条件培养基在盆栽试验中抑制了根结线虫卵的孵化，表现出杀线虫作用，并促进了植物生长。这些发现表明，所鉴定的化合物和条件培养基可为缺乏现有防治措施的作物提供一种新的线虫防治方法。
