Reação de Genótipos de Phaseolus vulgaris a Nematoides das galhas de clima tropical e temperado

Abstract

Along cycle of Phaseolus vulgaris, some soil pathogens attacks can occur, resulting in diseases that can drop the productivity. The root-knot nematodes are considered one of the main pathogens responsible for low productivity in common bean crops and snap bean. This soil pathogens can damage both in tropical and temperate climates, being a difficult control. Among the control practices of nematodes is the use of resistant cultivars as the more efficient. In this sense, we conducted two research activities in this work. The first had as goal a screening of the reaction of 64 genotypes of P. vulgaris against root-knot nematodes Meloidogyne incognita race 1 and M. javanica. To M. incognita race 1 were considered resistant bean genotypes Aporé, VP-25 and BRS Valente. Only Aporé was resistant to M. javanica. Ouro Vermelho, Radiante and HFFS 10793 had good resistance results to both M. incognita race 1 and M. javanica, suggesting that they are able, along with Aporé, to serve as resistance sources of these nematodes. In the second work we aimed to study the reaction of nine genotypes of P. vulgaris against the temperate nematode M. Chitwood and the tropical nematode M. enterolobii and also study the mechanism of resistance facing the tropical nematode M. javanica and M . incognita. The cultivars Aporé, BRS Campeiro, CVIII 2, EMB 4, Macarão Rasteiro, Talismã and VR 18 were highly resistant to M. Chitwood. For M. enterolobii, only VR 18 and Aporé cultivars showed a good result when compared to the susceptible control. Our results suggest that the development of M. javanica in the bean roots is slower than the species M. incognita. For both species of nematodes M javanica and M. incognita, cultivars VR 18, Talismã and Aporé had a good performance and can be used in P. vulgaris breeding programs. Aporé was considered a possible trap genotype to root-knot nematodes.