Preservação da capacidade reprodutiva de Meloidogyne exigua em mudas de pimentão

Abstract

Coffee is the host-type of Meloidogyne exigua and significant inoculum production on this plant takes a long time. The objective of this study was to evaluate the reproduction of five M. exigua populations on coffee comparatively with reproduction on pepper, and the possible occurrence of physiological selectivity after successive generations on pepper. In the selectivity test, one population was maintained on coffee and pepper for 30 months and reproduction was evaluated 10 times, at 90 day intervals. The number of galls and eggs was always higher in pepper roots than in coffee ones. The reproductive rate in pepper was four times higher than in coffee. There was no difference in nematode reproduction in coffee between the two inoculum sources, coffee and pepper, during 30 months. Pepper proved to be a better host than coffee for the rearing of M. exigua, including those populations unable to reproduce in tomato roots, since pepper plants are easy to manage under green-house conditions and nematode reproduction is faster than in coffee. Therefore, pepper should be used to rear M. exigua since the nematode does not lose its ability to infect coffee. Copyright by the Brazilian Phytopathological Society.