Hydrogen peroxide supplementation alleviates the deleterious effects of cadmium on photosynthetic pigments and oxidative stress and improves growth, yield and pods quality of pea (Pisum sativum L.) plants

摘要

The effects of foliar applied H2O2 on chlorophyll, carotenoids, the non-enzymatic defense system (ascorbic acid), malondialdehyde (MDA) hydrogen peroxide (H2O2) and growth were assessed in roots and shoots of pea (Pisum sativum L.) plants exposed to excess cadmium. In addition, we evaluated the influences of H2O2 spraying on proline, soluble sugars and soluble proteins contents. Excessive cadmium treatment caused reduction in the growth parameters (dry mass, pods and seeds dry weights), chlorophyll and carotenoids contents, roots total free amino acids, roots soluble sugars as well as shoots and roots soluble proteins levels but increased total free amino acids and soluble sugars contents in shoots. Concentrations of hydrogen peroxide and MDA was enhanced under Cd treatment. The foliar treatment of H2O2 alleviated the detrimental effects generated under Cd treatment that represented as increment in pea growth. H2O2 spraying increased photosynthetic pigments, growth characteristics, soluble proteins, and ascorbic acid contents comparing to the control sets not receiving H2O2. Similarly, a higher up-regulation was detected in proline contents of Cd+H2O2 set than Cd group ones at 0.25mM Cd. Contrarily, malondialdehyde (MDA), soluble sugars and total free amino acids contents of Cd+H2O2 set revealed a lower decrease than Cd group ones especially in roots. The results demonstrated that H2O2 treatment could inverse the harmful effects of cadmium on growth, through inducing the non-enzymatic defense system (ascorbate), proline accumulation, maintenance of chlorophyll in pea leaves and lowering the intensity of H2O2 and lipid peroxidation (MDA).