Associação de tratamento de sementes e resistência de cultivares de soja no controle de Meloidogyne javanica

Abstract

Root-knot nematodes are widespread disseminated in field crops in Brazil and responsible for expressive yield reductions, including soybeans. Management of nematodes represent a great challenge. The objective of this work was to evaluate the association of seed treatment with Avicta® Complete 400 mL p.c. kg-1 of seeds (abamectin 500 g L-1 , thiamethoxam 350 g L-1 , fludioxonil 25 g L-1 + metalaxyl-M 20 g L-1 + thiabendazol 150 g L-1 ) in soybean cultivars with different resistance reactions to the root-knot nematode (Meloidogyne javanica). The essay was carried out at the Plant Pathology Laboratory of UFGD. The experimental design was a completely randomized in a 2 x 4 factorial arrangement (with and without treatment). of seeds and 4 cultivars) with 10 replications. The cultivars M6410IPRO, BRS7380RR, BRS284 and BRS511 were submitted to seed treatment in a single dose and untreated control, which were sown in a M. javanica infested substrate. Twenty-one days after sowing, the plants were submitted to the following evaluations: height, fresh root mass, shoot dry mass. After root staining procedures, nematode counts were done. Seed treatment negatively affected nematode numbers in the roots of the susceptible cultivar Monsoy6410IPRO. The number of females and J3J4 number of nematodes in the roots of the resistant cultivar, BRS7380RR, were lower in plants under nematicide seed treatment. Moderately resistant BRS284 cultivar exhibited lower infective juveniles among the cultivars and BRS7380RR had lower J3J4 counts. Seed treatment, including abamectin, is an option in M. javanica management.