Reação de acessos de jerimum (Cucurbita spp.) a Meloidogyne incognita.

Abstract

Several native varieties of cucurbits are cultivated in Brazil, mainly by small and medium producers in the North and Northeast regions. However, losses caused by soil pathogens, such as root-knot nematodes, are significant. The objective was to evaluate the reaction of eight accessions of pumpkin (Cucurbita maxima) to the parasitism of Meloidogyne incognita. The experiment was carried out in a greenhouse and in the Plant Pathology Laboratory of the Federal University of Campina Grande - UFCG, Campus Pombal, in a completely randomized design, with ten treatments, with five replications. Each plot consisted of one plant per pot of 4 dm3 and kept in a greenhouse, inoculated with 4,000 second-stage eggs/juveniles of M. incognita. After 60 days of inoculation, the plants were evaluated for fresh root mass, root length, root volume, number of eggs and juveniles in the root, eggs and juveniles in the soil; nematode per gram of root; reproduction indexes (RI); reproduction factor (FR) and reproduction factor reduction (RFR). All jerimum accessions showed resistance to the M. incognita species when the reproduction index and reproduction factor criteria were used. However, when the reproduction factor reduction evaluation criterion was used, the accessions were only classified as moderately resistant. The results indicate the potential of jerimum accessions in breeding programs to identify the main genes that confer this resistance.