ABSTRACT Root-knot nematodes cause a significant reduction in the productivity of the gilo due to physiological stress. Incorporating organic residue into the soil has a positive effect in reducing nematode infestation. The aim of this study was to evaluate the effect of the addition of organic residue on the reproduction of Meloidogyne javanica and its role in the physiology of the gilo. One-litre pots, each containing one gilo seedling, were inoculated with 5000 eggs of M. javanica and the following treatments evaluated: 1) no inoculation and no residue (NIR); 2) NIR; 3) 12.5 g L-1 poultry manure; 4) 25 g L-1 cattle manure; 5) 20 g L-1 filter cake; 6) 5 g L-1 of the shoots of Tagetes patula; 7) 6.25 g L-1 of the shoots of Brassica oleracea var. capitata; 8) 20 mL L-1 vinasse and 9) 1 mL Abamectin-based commercial product (18 g L-1 a.i.). A randomised block design was used, with six repetitions. Gas exchange variables were evaluated 15, 30 and 45 days after inoculation with the nematode (DAI) and the vegetative and nematological variables at 60 DAI. The treatments that included cattle manure and filter cake afforded the best physiological rate and development in the gilo. The best results in controlling the nematode were given by the poultry manure, cattle manure and filter cake, reducing the reproduction of M. javanica by 41.76, 51.44 and 52.40%, respectively. Based on the results, poultry manure, cattle manure and filter cake are efficient in controlling M. javanica and show potential to be used in the integrated management of M. javanica in the gilo.

RESUMO: Problemas causados pelos nematoides-das-galhas, pertencentes ao gênero Meloidogyne podem ser controlados com a introdução de genes de resistência em cultivares comerciais de tomateiro. No entanto, plantas do híbrido ‘Heinz 9992’ adequadas ao processamento industrial, portadoras do gene Mi, foram encontradas com suas raízes severamente infectadas, em um cultivo experimental no município de Morrinhos (GO) com sintomas típicos de galhas causadas por Meloidogyne spp. Após dissecar as galhas presentes nas amostras de raízes, as fêmeas do nematoide foram retiradas para a análise do padrão perineal e a caracterização bioquímica por eletroforese de isoenzimas, além do teste de patogenicidade. O patógeno em estudo foi identificado como Meloidogyne incognita. O teste de patogenicidade confirmou que ocorreu a suplantação de resistência do híbrido de tomateiro, portador do gene Mi, por esta população virulenta de M. incognita.

ABSTRACT: Problems with root-knot nematodes, caused by genus Meloidogyne, can be controlled through the introduction of resistance genes in commercial varieties of tomatoes. However, plants of the hybrid ‘Heinz 9992’ for industrial processing, carrying the Mi gene, were reported with their roots severely infected in experimental cultivation in Goiás State of Brazil with symptoms typical of galls caused by Meloidogyne spp. After dissecting the galls present in the root samples, the females of the nematodes were removed and afterwards, performed the analysis of the perineal pattern and the biochemical characterization by electrophoresis of isoenzymes, besides the pathogenicity test. The pathogen analyzed was identified as Meloidogyne incognita. The pathogenicity test confirmed the supplanting resistance of the tomato hybrid with the Mi gene by this virulent population of M. incognita.