Prospection of genetic resistance resources to root-knot nematodes in cucurbit genotypes

The aim of this research was to prospect genetic resistant sources to root-knot-nematode in Cucurbitaceae accessions. Two assays were conducted, the first to evaluate the resistance to root-knot nematode, M. incognita race 1 in accessions of Lagenaria vulgaris; Sicana odorifera; Cucurbita facifolia; Luffa sp.; Citrullus lanatus cv. Citroides; Lagenaria vulgaris; Cucurbita moschata; Cucurbita moschata x Cucurbita maxima; Cucumis melo and Cucumis metuliferus. The second to evaluate the reaction to nematode M. incognita race 1, M. javanica and M. enterolobii of the three accessions of Cucumis metuliferus (`Kino') considered resistant to M. incognita race 1 in the first experiment. The assays were carried out in a greenhouse at Embrapa Hortalicas in a completely randomized design with six replications. The seedlings in pots were inoculated with 5000 eggs and juveniles of 2nd stage (J2) of each Meloidogyne species alone. Fifty-three and eighty-four days after inoculation, respectively in both experiments, the plants were evaluated for egg mass index (IMO), gall index (IG), number of eggs per gram of root (NEGR) and reproduction factor (RF). The melon Cucumis metuliferus known as 'Kino' was identified as genetic source of resistance to root-knot nematodes and can be explored in breeding program as resistant rootstock.