Heavy metal Cd affecting nodulation and leghaemoglobinproteins in soybean and chickpea

Abstract

Cadmium, one of the heavy metal soil pollutants, affects nitrogen fixing efficacy of legumes adversely. Nodulation in soybean reduces with Cd induced stress. The heavy metal effect in terms of root nodule
number gets substantiated in cumulative manner from vegetative to flowering to pod filling stage of the crop. Increased amino acid content of soybean root nodules was highest at flowering stage and dose dependent also. The increase in level of this metabolite also coincided with nodular senescence and age related changes. Leghaemoglobin content of root nodules lowers significantly both in soybean and chickpea with higher doses of Cd. Brown coloration of root nodules was an indicator of the Lb degradation noticed at flowering and pod filling growth stages in the presence of heavy metal. Such changes lower crop productivity due to ineffective nodulation and the lesser availability of nitrogen in Cd polluted soils