GENETIC-RESISTANCE TO ROOT-KNOT NEMATODE (MELOIDOGYNE-JAVANICA) IN EGGPLANT (SOLANUM-MELONGENA)

A germplasm collection of 39 eggplant Solanum melongena genotypes and one accession of S. torvum was evaluated for resistance to the root-kn ot nematode (Meloidogyne javanica) by using controlled greenhouse test s. Different degrees of resistance to the disease caused by this nemat ode species were observed among the genotypes tested. Complete resista nce (no nematode egg mass formation up to 7 weeks after inoculation) w as detected in one accession belonging to domesticated S. melongena sp ecies. Good levels of incomplete resistance were also observed in some commercial eggplant genotypes. This is apparently the first report of a source of complete resistance to M. javanica within the S. melongen a gene pool and our finding could greatly facilitate the incorporation of this trait into commercial eggplant cultivars. S. ron um, previous ly described as resistant to several root-knot nematode species (inclu ding M. javanica, M. arenaria, and M. incognita) was also confirmed as a source of resistance to this Brazilian population of M. javanica. T herefore, S. torvum can be considered as one of the most promising sou rces of broad-spectrum resistance genes against root-knot nematodes. B road-spectrum resistance is of paramount importance for breeding progr ammes focused on the development of cultivars for tropical and subtrop ical areas of the world where multiple infestation of soils with disti nct Meloidogyne species is a very common feature.