Effects of Irrigation Quota on Photosynthetic Characteristics, Yield, and Water Utilization of Spring Maize in Semi-Arid Region

The response of maize yield, water utilization and photosynthetic physiological characteristics to irrigation was studied systematically, which provided an effective irrigation method for semi-arid areas in western Jilin province. The irrigation quota was set as 2500,1700,900 and 0 m(3)/hm(2) (CK). Effects of irrigation quota on maize yield and yield formation factors, water utilization, photosynthetic and chlorophyll fluorescence characteristics on different periods were studied. The results showed that the yield, grain weight of 100 grains and ear number were all significantly increased in 2500 m(3)/hm(2) and 1700 m(3)/hm(2) treatment compared with CK. With the increase of irrigation quota, the water consumption of maize showed a trend of 2500 m(3)/hm(2)>1700 m(3)/hm(2)>900 m(3)/hm(2)>CK. The water productivity (WUE) of 1700 m(3)/hm(2) treatment was the highest. The net photosynthetic rate, stomatal conductance, transpiration rate, intercellular CO2 concentration and apparent mesophyll conductance of 2500 and 1700 m(3)/hm(2) treatment significantly increased compared with CK. The stomatal limitation showed the trend of CK>900>1700>2500 m(3)/hm(2). The PSII maximum photosynthetic efficiency, actual photosynthetic efficiency of PSII of 2500 m(3)/hm(2), 1700 m(3)/hm(2) treatment also significantly increased compared with CK. The photochemical quenching significantly increased and the non-photochemical quenching significantly decreased compared with CK. Analysis showed that when the irrigation quota of 1200 m(3)/hm(2) was fixed during the growth period, its yield, water utilization and photosynthetic physiological characteristics were the best. It is concluded that the irrigation amount of 1200 m(3)/hm(2) can be the best irrigation quota in the western semi-arid area of Jilin Province. (C) 2019 Friends Science Publishers