"以肥调水"缓解干旱对无膜滴灌棉花生理特性和产量的影响OA北大核心CSTPCD

[Objective]This study aims to investigate the regulatory effect of"fertigation adjusted water management"on the physiology and the growth of drip-irrigated cotton in alleviating drought stress,and to enhance cotton yield under limited water resource.[Methods]Using Zhongmian 619 as the test material,two types of irrigation quotas for deficient irrigation(W1:45 mm)and full irrigation(W2:54 mm)in combination of three nitrogen input doses,including low nitrogen(F1:150 kg· hm-2),medium nitrogen(F2:225 kg·hm-2),and high nitrogen(F3:300 kg·hm-2)were set.The effects of different irrigation quotas and nitrogen doses on cotton physiological growth indicators and seed cotton yield were analyzed.[Results]The results indicated that increased irrigation quotas promoted cotton growth,enhanced two-year average leaf area index(LAI),relative chlorophyll content(soil and plant analyzer development,SPAD value),and net photosynthetic rate(Pn),while redued the activities of cotton superoxide dismutase(SOD),catalase(CAT),peroxidase(POD),and malondialdehyde(MDA)content.With the increase of nitrogen application,LAI,SPAD,Pn,and antioxidant enzyme activity were increased,MDA content was decreased on average,and the influence of water deficiency on cotton development was alleviated.Under W1 treatment,increased nitrogen application improved cotton yield,while under W2 treatment,cotton yield showed the trend of increasing first and then decreasing with the increase of nitrogen application.Under water-nitrogen interaction,the highest two-year average seed cotton yield(6 821.86 kg·hm-2)was recorded under W2F2 treatment followed by W1F3 treatment(6 717.72 kg·hm-2).In the technique for order preference by similarity to ideal solution(TOPSIS)analysis,the comprehensive scores of W1F3 and W2F2 were 0.57 and 0.56,respectively,and the differences between the two-year yield of W1F3 and W2F2 treatments were not significant.[Conclusion]Increased nitrogen application under deficit irrigation effectively alleviates the adverse effects of drought on the physiological characteristics and yield in cotton.It is recommended to use 45 mm irrigation quota combined with 300 kg·hm-2 nitrogen application as the fertigation strategy for the filmless drip-irrigated cotton in southern Xinjiang,to effectively ensure cotton yield under limited water resource.