Toxic effect of Zinc on growth and nutrient accumulation of cow pea (Vigna unguiculata L.)

Zinc is a heavy metal; this element is considered as environmental hazard.Toxicity effects of Zinc on growth and development of plants including inhibition of germination process decrease of growth and biomass of plant. The aim of this research is to study accumulation of Zinc along with nutrients and its effect on the growth of Cow pea plant (Vigna unguiculata.L). Thus, cow pea seedlings grown in petriplates lined with filter paper undergoing, different treatments of Zinc (control, 10, 25, 50, 75, 100, 150 and 200 ppm). After one week seedlings were removed and morpho physiological parameters like root length, shoot length and dry weight of plants and accumulation of nutrients along with Zinc in roots and shoots were determined. The results indicated that the concentrations more than Zinc 50 mg/L zinc cause the reduction of morphophysiology parameters in the treatment plants rather than control plant and zinc addition in the cultures caused enhancement of zinc content in roots and shoots of cow pea seedlings. Similarly nutrient accumulation also affected by increasing concentrations of cow pea. It was also noted that accumulation of zinc in the roots was much higher than the shoots of the seedlings under treatment.