为了建立适宜当地干旱生境下棉花膜下滴灌节水栽培参考标准模式,在甘肃省民勤特早熟棉区选择试验点,以‘酒棉8号’棉花新品种为试验品种,在每公顷18万株～33万株密度下,设2250 m3/hm2、2550 m3/hm2、2850 m3/hm2、3150 m3/hm2、3600 m3/hm2和4200 m3/hm26个全生育期不同滴灌量处理,应用WET-HH2型土壤水分温度电导率速测仪,在每次定额滴灌2天后测定20 cm、40 cm、60 cm、80 cm和100 cm 5个不同土层的体积含水量（VWC）,观测土壤VWC下降至20%时所需的间隔天数。结果表明,20～60 cm土层VWC受自然蒸发和棉花植株蒸腾失水的影响明显,在3600 m3/hm2滴灌量下,籽棉产量最高,平均达到每公顷4414.5 kg,为民勤特早熟棉区适宜的膜下滴灌量。在生产中可供参考的标准膜下滴灌模式为：全生育期共滴灌8次,首次在6月20日,末次在8月30日,每次滴灌定额为300～525 m3/hm2,不同生长时期滴灌的间隔时间为8～15天。%Total of six drip-irrigation volumes（m3） per hectare including 2250 m3,2550 m3,2850 m3,3150 m3,3600 m3 and 4200 m3 were determined for the water physiology study of a new cotton cultivar‘Jiumian8’ under the 180000-330000 plants per hectare of the cultivating density in the experimental field choiced at Minqin of Gansu Province.After two days of each drip-irrigation,the volume water content（VWC） under the soil layers of 20 cm,40 cm,60 cm,80 cm and 100 cm were measured by the WET-HH2 conductivity meter of the soil water and temperature,respectively.Then The standards mode was established for local drought habitat under drip irrigation by observing the interval time when soil VWC dropped to 20%.The results showed that the VWC under the soil layers from 20 cm to 60 cm significantly suffered from the soil natural evaporation and the transpiration of cotton plants.The yield of the seed cotton was highest up to 4414.5 kg per hectare under the 3600 m3 of drip-irrigation volumes per hectare,which was the optimal drip-irrigation volume for the special early maturing cotton area in Minqin.In the production of standard drip irrigation mode was： total of 8 times of the drip irrigation in the whole growth stages was from the first time 20,June to the last time 30,August,drip-irrigation 300-525 m3 per hectare and drip-irrigation intervals was 8-15 days at different growth stages.
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