Effect of chromium on basic growth factors of Pennisetum glaucum L.

Abstract

One of the main concerns of agricultural production is heavy metal pollutants. The industrialization has resulted in the heavy metal contamination of agricultural soil and ecosystems. Metals are a natural component of the earth,  it is when their concentration increases from natural levels, ecological deterioration occurs. In the present study, transplant experiments were conducted to evaluate the effect of chromium-contaminated soil in Pennisetum glaucum L. The seeds growing in petridishes were exposed to chromium, in increasing concentrations of 1, 3, 5, 10, 50, 100, 200, 300, 500 ppm. Each treatment was replicated in a randomized design and observed over a period of 7 days. The seedlings were studied for their response based on germination rate, seed vigour index, length of the radicle, length of plumule, and fresh weight against seeds germinated using distilled water as a control. Five different chromium concentrations i.e., 5, 10, 50, 100 & 200 ppm, were applied to the plants. Each treatment was replicated in a randomized design and observed for 45 days. The plants were studied for the length of root, length of shoot, fresh weight, total chlorophyll content, protein content, and heavy metal analysis compared to a set irrigated using distilled water as a control. The root and shoot lengths decreased with an increase in Cr concentrations in the transplants. A gradual decrease was observed in the selected parameters, with an increase in Cr levels. The values related well with increased Phyto-accumulation of chromium within the tissues of both roots and shoots. It was observed that chromium's harmful effects on all the parameters were directly proportional to the concentration of solution employed, with the inhibition of growth being more pronounced from 50 ppm onwards. As Pennisetum glaucum L. an edible crop despite showing a good potential for application in phytoremediation techniques, it can’t be used to hyper accumulate chromium to remove it from the soil.