Evaluation of some cucurbitaceous rootstocks for resistance or susceptibility to root-knot nematode and fusarium wilt under greenhouse conditions

Abstract

Southern root-knot nematode, Meloidogvne incognita and Fusarium wilt Fusarium oxysporum are the most serious soil bome diseases of cucumber. The present study aimed to evaluate some cucurbit rootstocks for their resistance and/or susceptibility to root-knot nematode and fusarium Wilt fungus m two successive seasons (2009 and 2010) under greenhouse conditions. Data indicated that in autumn season, winter squash (Cucurbita maxima) was highly resistant and resistant when the pots were inoculated with M. incognita only or nematode plus fitngus, respectively. Lagenaria sicenaria rootstock was moderately resistant in both cases of inoculation. Other rootstocks were susceptible to nematode or nematode plus fungus except Cucurbita ficifolia and Lufa aegvptiaca, which were highly susceptible to nematode only. While, in spring season, Benincasa hispida and hybrid 6001 were moderately resistant to infection by the root-knot nematode Other rootstocks were susceptible to nematode or nematode plus fitngus except Lufa acutangula and Cucumis sativus var. Hesham which were highly susceptible. The results obtained on the enzyme content showed that some cucurbit footstock; exhibited the highest content of polyphenoloxidase, peroxidase and llgmn contents being the lowest in some rootstocks. Significant and highly significant reductions in shoot and root fresh weights, root and shoot lengths were recorded in most cucurbit rootstocks in autumn and spring seasons as a result of nematode, nematode plus fungus or hungus infections compared to non-infected rootstocks_