Reaction of soybean genotypes to the nematodes Meloidogyne incognita and M. javanica

Abstract

Brazil is the world's largest producer and exporter of soybean and studies show that production will continue to grow in the coming years. However, this increase is considered a major challenge due to the serious damage and losses caused by nematodes. The use of resistant materials presents a sustainable alternative for suppressing them. Therefore, the objective was to evaluate the reaction of soybean genotypes to populations of Meloidogyne incognita and M. javanica. Two experiments were carried out for each species, on different dates, under greenhouse conditions, in a randomized block design with ten and twenty-two treatments, respectively, and four replicates. Plants were inoculated ten days after planting with a suspension of 2500 eggs and second-stage juveniles of M. incognita and M. javanica. Evaluations took place sixty days after inoculation (DAI), determining plant height, stem diameter, Spad index, leaf area index, reproduction factor and reproduction factor reduction. For the species M. incognita all genotypes were susceptible. The UFUL 592 and UFUL 298 genotypes had greater vegetative development and the UFUL 526 genotype behaved as a good host for the nematode. For M. javanica, the UFUL 172 and UFUL 592 genotypes showed good performance in terms of growth parameters, as well as nematological ones. In general, the UFUL 592 genotype performed well in the four trials.