Effects of cadmium stress on seedlings of various rangeland plant species (Avena fatua L., Lathyrus sativus L., and Lolium temulentum L.): Growth, physiological traits, and cadmium accumulation

摘要

A pot culture experiment was performed to study the effect of cadmium stress (Cd stress) on seedling growth, physiological traits, and remediation potency of Avena fatua, Lathyrus sativus, and Lolium temulentum. The seedlings of these native rangeland plant species were treated with 0, 2, 4, and 6 mM cadmium nitrate concentrations. Based on the results of analysis of variance (p 0.05), the shoot height, shoot dry weight, root length, root dry weight, root: shoot ratio, total chlorophyll content, soluble sugars, and protein contentof A. fatua, L. sativus, and L. temulentum significantly decreased with increased cadmium concentrations. Generally, translocation factor (TF) and tolerance index (TI) decreased significantly as the concentration of cadmium increased. The maximum TF and TI of studied plants in various concentrations of Cd were observed in L. temulentum followed by L. sativus and A. fatua. The root concentration factor (RCF) values of all studied plants were higher than 1 under different cadmium concentrations. Our results indicate that Lolium temulentum could be labeled as an accumulator of Cd asthe values of TF and RCF are greater than 1. A. fatua and L. sativus showed a potential to be used in the phytoremediation of Cd-contaminated soils.