Study On Optimizing Potato Irrigation Schedule By Adjusting Deficit Of Drip Irrigation Under Film

The experiment was conducted in 2017 at Wenshui County Central Irrigation Test Station of Luliang City,Shanxi Province.According to different water regulation deficit levels and growth stages,seven treatments(T1-T7)were set up to regulate water deficit at seedling stage,seedling stage,seedling stage,tuber-setting stage and starch accumulation stage,respectively,for mild(60%-70%)and moderate(50%-60%)water regulation deficit.This experiment analyzed the effects of different water regulation deficits on water consumption characteristics,yield,water use efficiency and growth dynamics of potatoes in different growth stages.A water production function based on Jensen model was established and potato irrigation system was optimized.The main conclusions were as follows:(1)The effect of drip irrigation deficit under Mulch on soil temperature during potato growth period was greater at seedling stage,seedling stage,seedling stage and potato-setting stage,while the effect of starch accumulation period was not significant.(2)The depth of influence of drip irrigation deficit under Mulch on soil moisture of potato ranged from 0 to 40 cm,but the effect of soil moisture in 40 to 100 cm layer was not significant.The water consumption of potatoes was the highest in potato growing stage,followed by starch accumulation stage,seedling stage and heading stage,and the lowest in emergence stage.(3)Under drip irrigation under mulch,moderate water deficit regulation during potato setting stage has a significant effect on yield.Full irrigation at potato setting stage and moderate water deficit regulation at other growing stages are beneficial to yield improvement.(4)The leaf area index of potato was the largest at potato-bearing stage,followed by starch accumulation stage and the smallest at seedling stage.Using genetic algorithm and water production function to optimize irrigation schedule,the results showed that the highest yield was 1997.08kg/mu when the irrigation quota of potato under mulch drip irrigation was 225 mm during the whole growth period in Shanxi Province.Irrigation schedule is 20 mm at seedling stage,70 mm at heading stage,115 mm at tuber-setting stage and 20 mm at starch accumulation stage.