Effect of heavy metals and sewage on seed germination and plant growth

Abstract

In present study Pea, Pigeon pea were taken as experimental plant in order to study effect of sewage irrigation on germination and growth of plants. Deleterious effect of heavy metal on seed germination, protein, sugars, hydrolytic enzyme activities were studied. Concentrated sewage and higher concentration of heavy metal produce adverse effect on germination, alongwith other parameters i.e. protein, sugar and enzyme activity. Maximum deleterious effect was in 100% sewage concentration and 3-5 mM of heavy metals. The field work was conducted and it was found that heavy metals are present in sewage effluent, mostly in prescribed limit with few crossing the limits. With continuous irrigation, metals get accumulated on the soil with decreasing amount with the depth. The crops grown on such lands and irrigated with sewage effluent, showed higher plant growth but most of the parts of plant were found to be containing heavy metals in higher amount compared to the plants grown on tube well irrigated fields. It is predictive that with continuous exposure and irrigation the amount of heavy metal would keep on increasing in plant and thus would affect the food chain mainly the humans.