Regulation of Melatonin on Photosynthetic Characteristics and Antioxidant Enzyme Activities in Maize Leaves under High Temperature Stress Condition
In 2022,Anke 985 was used as the experimental material.Under the condition of natural high tem-perature stress at the filling stage of maize(long duration,wide range,high intensity and strong extremeness of high temperature in summer of 2022),different concentrations of melatonin(MT)solution 0(CK),100(MT100),200(MT200),300(MT300)μmol/L were set to study the effects of different treatments on photosynthetic characteristics,fluorescence characteristics,antioxidant enzyme activities and yield formation of maize leaves.The results showed that Melatonin treatment significantly increased the number of kernels per row,ear diameter,ear length,100-grain weight and yield per plant,and decreased the length of bald tip.Ccompared with the control.The SPAD value,N content,net photosynthetic rate,stomatal conductance and transpiration rate of leaves increased significantly after melatonin treatment,and the intercellular carbon dioxide concentration decreased significantly.Compared with the control,ΦPSⅡ,ETR,qN,qP and Fv/Fm were significantly increased under melatonin treatment.Compared with the control,and Y(N0)and F0 decreased significantly.The antioxidant enzyme activities(SOD,POD,CAT)of leaves were significantly increased by 200 μmol/L treatment,and the MDA content was significantly decreased.After mela-tonin treatment,dry matter accumulation and dry matter distribution to grains increased significantly.Under natural high temperature stress,melatonin treatment can enhance maize resistance,and 200 μmol/L is the best.
MaizeMelatoninNatural high temperaturePhotosynthetic fluorescence characteristicAntioxi-dant enzymeYield
NETL
NSTL
万方数据
