Meloidogyne exigua: distribuição espacial, nível de infestação, mortalidade de seringueiras e controle com plantas antagonistas

Abstract

The infestation of nematodes of the genus Meloidogyne is one of the main limiting factors for the expansion of Brazilian rubber tree plantations. Previous studies have shown that this root-knot nematode affects growth of the rubber tree, thus reducing the development of trees in the production phase and even jeopardizes its survival. In this context, the objective of this study was to evaluate the spatial distribution of Meloidogyne exigua in a rubber tree plantation and its control with antagonistic plants. In order to perform this, two experiments were done. The first one evaluated the population density of the root-knot nematode in a commercial rubber tree plantation in Triângulo Mineiro, Minas Gerais. The population density of M. exigua, in the studied area, was concentrated in elliptic foci with a clustered spatial distribution. The second experiment evaluated the effect of the antagonistic plants Arachis repens, Brassica juncea, Brassica napus, Crotalaria spectabilis, and Tagetes sp. on the management of M. exigua in rubber tree seedlings. Both Brassica juncea and Arachis repens showed antagonistic effect on nematode population. The results obtained highlight the importance of proper nematode management for the expansion of Brazilian rubber tree plantations.