Evaluation of allyl isothiocyanate as a soil fumigant against soil‐borne diseases in commercial tomato (Lycopersicon esculentum Mill.) production in China

Abstract BACKGROUND Root‐knot nematodes ( Meloidogyne spp.), soil‐borne diseases and weeds seriously reduce the commercial yield of tomatoes grown under protected cultivation in China. Allyl isothiocyanate (AITC), a natural product obtained from damaged Brassica tissues, was evaluated as a potential replacement for the fumigant methyl bromide (MB) for use in the greenhouse production of tomatoes in China. RESULTS The dose–response assay indicates that AITC has high biological activity against major bacterial and fungal pathogens (EC 50 of 0.225–4.199 mg L −1 ). The bioassay results indicate that AITC has good efficacy against root‐knot nematodes (LC 50 of 18.046 mg kg −1 ), and moderate efficacy against fungal pathogens (LC 50 of 27.999–29.497 mg kg −1 ) and weeds (LC 50 of 17.300–47.660 mg kg −1 ). The potting test indicates that AITC significantly improved plant vigor. Field trials indicate that AITC showed good efficacy against Meloidogyne spp. and Fusarium spp. (both ∼ 80%) as well as Phytophthora spp. and Pythium spp. (both ∼ 70%), and improved plant vigor and marketable yield. CONCLUSION AITC used as a soil fumigant (30–50 g m −2 ) effectively controlled major bacterial and fungal pathogens, root‐knot nematode, weeds and increased plant vigor, yield and farmers' income in tomato cultivated under protected agriculture in China. © 2018 Society of Chemical Industry