Effect of Zinc on Seed Germination, Coleoptile Growth and Root Elongation of Six Pulses

Abstract

The ecotoxicological effects of Zn2+ on germination and early seedling growth of six pulses were investigated. Seeds of these plants were exposed to seven different concentrations of Zn (0, 0.2, 0.4, 0.8, 1.6, 3.2, and 6.4 mM). The results indicated that root growth and shoot elongation of six pulse plants were more sensitive than seed germination and dry weight for measurement of the toxic of Zn2+ pollutions. Different species show different levels of tolerance to Zn2+ pollution. Vigna radiate and Lathyrus odoratus are the most sensitive to Zn2+, their germination percentage, root growth, shoot elongation and dry weight were significantly lower than other tested species, by contrast, Glycine max and Dumasia villosa are the most resist species, their germination and seedling growth almost were not influenced by Zn2+ pollution significantly comparing the control. There were significantly negatively correlations between seedling growth and increasing concentration of Zn2+ for Glycine max, Lathyrus odoratus and Dumasia villosa. The significantly negative correlations between germination and increasing concentration of Zn2+ were show for Lathyrus odoratus.