Vam for root knot nematode management and increased productivity of grain legumes in Orissa

In an investigation involving VAM fungus, Glomus fasciculatum, legume bacterium Rhizobium phaseoli (M-14 strain) and roots knot nematode Meloidogyne incognita on green gram (Vigna radiata) alone and in various combinations, it was observed that all plant growth parameters including pod yield, leaf chlorophyll content, bacterial nodulation, leghaemoglobin content of nodules and NPK contents of plant were lower in nematode inoculations compared to control with significant improvement in mycorrhizal and rhizobial inoculations either alone or in combinations. Mycorrhizal and rhlzobial inoculations alone were superior over control in the absence of root-knot nematode, their combined inoculations giving better results than their single inoculations, showing a compatible and synergistic relationship between the two organisms with common antagonism to the root knot nematode. Root-knot nematode on the other hand suppressed the growth of other two organisms also. Increases in pod yields in mycorrhiza + nematode and rhizobium + nematode treatments were 44% and 22% respectively over that of nematode inoculations alone and 13%, 26% and 66% over control in nematode free soil due to mycorrhiza, rhizobium and mycorrhiza + rhizobium combinations respectively.