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通过盆栽试验在棉花不同生育时期进行不同程度的调亏灌溉试验。结果表明,调亏灌溉对棉花株高、蕾铃脱落、成桃数等影响较显著;苗期和吐絮期重度水分亏缺、蕾铃期中度水分亏缺均有利于棉花产量的形成。棉花的光合速率和气孔阻力随土壤含水量变化的阈值约在14％土壤含水量水平,该阈值相当于田间持水量的60％～65％。合理的棉花调亏灌溉制度是苗期控制水分供应,土壤含水量维持在田间持水量的55％～60％;雷期和花铃期是棉花的需水关键期,土壤含水量应分别保持在田间持水量的65％和70％左右;吐絮期应控制水分供应,土壤含水量维持在田间持水量的50％～55％。
Pot experiments were conducted to investigate the effects of different regulated deficit irrigation experiments at different growth stages of cotton. The results showed that the regressive deficit irrigation had significant effects on the plant height, the buds falling off, the number of peaches, etc. Severe water deficit at seedling stage and boll opening stage and moderate water deficit at budding stage were all favorable to the cotton yield. The threshold of photosynthetic rate and stomatal resistance with soil water content of cotton is about 14% of soil water content, which is equivalent to 60% -65% of field capacity. Reasonable cotton regulatable deficit irrigation system is to control the water supply at seedling stage, and the soil water content is maintained at 55% -60% of the field water holding capacity. The bolting period and bollwering period are the critical periods of water requirement for cotton and the soil water content should be kept at Field capacity of 65% and about 70%; boll opening period should control the water supply, soil moisture remained at field capacity of 50% to 55%.