Exogenous Nitric Induced Physiological Response of Capsicum annuum L.Under UV-B Stress

In this study, the effects of different concentrations of exogenous nitric donor sodium nitroprusside（SNP） on physiological characteristics of Capsicum annuum L.under UV-B stress was studied using pepper in fruit period in order to procide a scientific basis for Capsicum annuum L.cultivation and production.The results showed that under UV-B stress, spraying SNP(3 mmol·L^-1) significantly increased photosynthetic pigment content, photosynthetic fluorescence parameters Fv/Fm, antioxidant enzyme activities（SOD,POD,CAT） and soluble sugar content in Capsicum annuum L.leaves.Photosynthetic fluorescence parameters Fo and MDA content were significantly reduced; thereby alleviating the damage of chili by UV-B radiation.Exogenous nitric participates in the response and defense of Capsicum annuum L.to UV-B stress, increases the resistance of Capsicum annuum L.to UV-B stress.