Abstract

N.A.Tamilselvi* , L.Pugalendhi and M.Sivakumar

Root knot nematodes are responsible for severe crop loss in bitter gourd to the tune of 38-48.2%. Pot culture experiments were conducted under glasshouse conditions to study the effect of root knot nematode, Meloidogyne incognita Kofoid and White in ten cucurbitaceous species and to identify resistant rootstocks for grafting in bitter gourd. Second stage juveniles of M. incognita were inoculated at 2J2 per cc soil into the rhizosphere of 21 days old seedlings. Results revealed that, three genotypes viz.,Kumatikai(Citruluscolocynthis), African horned cucumber (Cucumismetuliferus) and pumpkin (Cucurbita moschata) showed resistant reaction followed by two rootstocks viz.,Sponge gourd (Luffa cylindrica) and mithipakal (Momordicacharantia var. muricata) which are moderately resistant. The biochemical activities viz., Polyphenol oxidase (PPO), peroxidase (PO) and phenylalanine ammonia lyase (PAL) showed superiority in the aforementioned species. These rootstocks are further used for grafting with bitter gourd scions.