Damage induced by root-knot nematodes and its alleviation by vesicular arbuscular mycorrhizal fungi in roots of Luffa cylindrica

The effect of vesicular arbuscular mycorrhizal (VAM) fungi inoculated with nematodes in roots of Luffa cylindrica (L.) Roem was studied under greenhouse conditions. Six treatments were used; viz., C = Control, T_1 = VAM only, T_2 = nematodes only, T_3 = VAM and nematodes simultaneously, T_4 = VAM fungi one week before nematodes and T_5 = VAM fungi one week after nematodes. Damage produced by nematodes was observed in T_2 and T_5, vascular tissue obliterated by root-knot nematodes. However, VAM fungi suppressed the effects of root-knot nematodes in T_4. Giant cells, egg-masses and females of nematodes were observed in T_2, T5 and to some extent in T_3. VAM fungi spores were seen in cortical as well as in pith region of root in T_3.