Botany Department, Lucknow University, Lucknow-226007.
Two genotypes viz. UPV -1and T9 of black gram (Vigna mungo L.) were tried for their susceptibility to low manganese when grown in refined sand at deficient (0.1 and 1.0 μM)and adequate (10 μM) manganese. Apart from growth depression the manganese deficiency symptoms appeared on middle leaves as severe interveinal chlorosis, later minute greyish brown spots developed on them which eventually turned dark brown and necrotic. Manganese deficiency relatively affected the flower and pod formation in both genotypes. Deficiency of manganese reduced the biomass, seed yield, Hill reaction activity, contents of chlorophyll a and b, leaf manganese, protein nitrogen, sugars and starch and accumulation in non-protein and nitrate nitrogen concentrations. In black gram leaves, the activity of ribonuclease was increased and that of catalase, peroxidase, aldolase, malate dehydrogenase ana acid phosphatase were decreased in low manganese. In seed of black gram,low managanese reduced the contents ofsugars, starch and total proteins and increased that of nitrate-nitrogn and phenols thus deteriorating the seed quality. The effect of manganese deficiency on all the parameters were more pronounced in genotype UPV-1 than in genotype T9 of black gram.
Black gram, enzymes, manganese deficiency, susceptibility
