Mineral Constituent Variations under Cobalt Treatment in Vigna mungo (L.) Hepper

A study was carried out to understand the mineral constituent variations under cobalt treatment in Vigna mungo (L.) Hepper. The experiments were conducted in earthen pots and lined the inner surface with polythene sheet. Each pot contains 3 kg of air dried soil. Blackgram plants were raised in these pots containing soils amended with different concentrations of cobalt (0, 50, 100, 150, 200 and 250 mg/kg). Plants were watered to field capacity daily. Plants were thinned to a maximum of six per pot. The various mineral contents were estimated on 30 days after sowing (DAS). Mineral contents such as nitrogen, th phosphorus, potassium, copper, manganese, iron and zinc contents were analysed in both control and treatments. All the mineral contents were increased at 50 mg/kg cobalt level in the soil, when compared with control. Further increase in the cobalt level (100-250 mg/kg) in the soil decreased all the mineral content of blackgram plants.