Effects of UV-B Radiation on the Growth,Resistance Physiology,and Metabolites of Polygonatum kingianum Seedlings
In order to investigate the physiological response mechanism of Polygonatum kingianum seedlings to UV-B radiation,the biomass,antioxidant enzyme activity,MDA and flavonoid contents of P.kingianum seedlings were measured after 0 to 25 days of treatment under the UV-B radiation intensity of 540 mw/cm2 every 5 days.The results show that under UV-B radiation,the plant height and chlorophyll content of P.kingianum seedlings show a downward trend,and with the extension of radiation time,the effect is more obvious.The effect of UV-B radiation on POD and SOD activity shows an increasing trend,while in the middle of UV-B radiation,compared with CK,it increases significantly.The effect on MDA content shows a trend of increasing first and then decreasing.The carotenoid content in leaves and flavonoid content in leaves and tubers increase with the extention of UV-B radiation time.In conclusion,UV-B radiation treatment could inhibit the growth of P.kingianum seedlings,increase an-tioxidant enzyme activity and flavonoid content,and enhance the resistance of P.kingianum to UV-B radiation.