基于田间持水量的水分下限调控对新疆棉花生长发育和产量形成的影响OA

To investigate the mechanisms by which different lower limits of irrigation affect the growth,development and yield formation of cotton in Xinjiang.This study involved a two-year field trial conducted in the Karamay region of Xinjiang.Two irrigation thresholds were established based on field capacity(FC),namely the 50%FC and 70%FC treatments.Various growth parameters,above-ground dry matteryield,boll and bud drop characteristics,and yield components were measured during the boll-opening stage.The results showed that the 50%FC treatment caused cotton to enter each growth stage earlier.Compared with the 70%FC treatment,the 50%FC treatment brought forward the budding,flowering,boll-setting,peak boll-filling and boll-opening stages by 2-3 days,2-4 days,3-6 days,2-5 days and 6-8 days,re-spectively.70%FC treatment promotes cotton growth and dry matter accumulation.Compared with the 50%FC treatment,plant height in the 70%FC treatment increased by 8.87%(2024)and 10.26%(2025),stem diameter increased by 9.56%(2024)and 7.54%(2025),and dry matter yield increased by 17.86%(2024)and 30.15%(2025)(P<0.05).The 70%FC treatment increased the boll-setting capaci-ty of the cotton.Compared with the 50%FC treatment,the 70%FC treatment resulted in increases of 4.60%(2024)and 7.11%(2025)in the number of fruiting spurs,the number of fruiting branches,and the proportion of fruiting branches,respectively;increases of 20.43%(2024)and 27.36%(2025);17.11%(2024)and 17.00%(2025)(P<0.05),respectively,whilst the number of fruits set increased by 23.94%(2024)and 21.80%(2025)(P<0.05).The 70%FC treatment increased both lint yield and irrigation water use efficiency.Compared with the 50%FC treatment,the 70%FC treatment resulted in increases in raw cotton yield of 14.04%(2024)and 15.51%(2025),and increases in irrigation water use efficiency of 7.33%(2024)and 6.92%(2025)(P<0.05).In summary,treatment with 70%FC promotes cotton growth and improves boll-setting,thereby increasing raw cotton yield and the efficiency of irrigation water use.Therefore,in the irrigation management of cotton in Xinjiang,taking into account local water resource conditions,it is recommended that 70%of FC be adopted as the appropriate lower limit for irrigation in or-der to achieve high and efficient cotton yields.