[Effect of zinc sulphate and PEG priming on ageing seed germination and antioxidase activities of Perilla frutescens seedlings].

Objective: To explore the method for improving the aging resistance of seeds and seedlings of Perilla frutescens through study on seed germination and physiological characteristics of P. frutescens seedlings.
Method: Several physiological indexes of P. frutescens seeds treated by different concentrations of ZnSO4 and PEG were measured. And other indexes like the activities of malondialdehyde (MDA), superoxide (SOD), peroxidase (POD) and catalase (CAT) were also determined.
Result: The germination indexes of P. frutescens aging seeds treated by different concentrations of ZnSO4 and PEG were all increased. And the seeds that treated by ZnSO4 (600 mg x L(-1)) and PEG (20%) showed the most significantly increase in every index. The germination vigor were 64.7% and 66.8%, the germination rate were 78.7% and 79.4%, the germination index were 11.8 and 12.2, the vigor index were 0.091 1 and 0.0939 respectively. The content of MDA was decreased under different treatment. The activities of three enzymes include SOD, POD and CAT were increased by different treatment of ZnSO4 (0.28, 4.71, 3.82 U x mg(-1) respectively) and PEG (0.29, 4.93, 4.18 U x mg(-1) respectively).
Conclusion: ZnSO4 with concentration of 600 mg x L(-1) and PEG with concentration of 20% could significantly alleviate the damages to the seeds and seedlings of P. frutescens by aging and promote the aging resistance of the seeds and seedlings.