水分调控对麦茬棉产量和水分利用效率的影响

为研究麦后移栽棉对水分调控的响应,于2012年6月~2012年10月通过人工控水试验研究了水分供应对麦后移栽棉生长、产量和品质的影响。小区试验结果表明,蕾期轻度水分亏缺花铃期充分灌水处理(T2)的籽棉产量、成铃数以及单铃质量均为最大,但蕾期和花铃期轻度水分胁迫处理(T4)的产量与处理T2差异不显著,但水分利用效率和灌溉水利用效率分别提高了23.93%和34.01%;管栽试验结果表明,对照处理(T7)的单株成铃数的收获籽棉产量均最高,与对照处理相比,全生育期轻度水分胁迫处理(T8)减产3.98%,水分利用效率和灌溉水利用效率分别提高了9.70%和20.02%;桶栽试验结果表明,灌水定额为1.6倍ETp处理(T11)的籽棉产量和单株成铃数均最高,与处理T11相比,灌水定额为1.3ETp处理(T12)的籽棉产量仅降低了9.7%,而灌水定额为1.0 ETp处理(T13)的籽棉产量降低了30%。说明适宜的水分胁迫(灌水下限为60%~65%FC,灌水上限为80%~85%FC)有利于麦后移栽棉的高产和水分利用效率的提高。

Effects of Different Water Treatment on Yield and Water Use of Transplanted Cotton Following Wheat Harvest

Water regulation has important influence on intransplanted cotton following wheat harvest. To investigate a suitable irrigation schedule of intransplanted cotton following wheat harvest, an experiment was conducted to study the effects of different water treatments on the water consumption, seed yield, water use efficiency and quality of intransplanted cotton following wheat harvest. Three irrigation level 45%~50%, 60%~65% and 75%~80% FC were set as lower limit of soil moisture for plot experiment under a rainproof canopy at squaring stage and blooming-boll forming stage, respectively. 80%~100% FC (T7), 60%~80% FC (T8), 50%~90% FC (T9) and 40%~60% FC (T10) were set for pipe experiment from seeding stage to boll opening stage, respectively. Five irrigation quota treatments, 1.6 (T11), 1.3 (T12), 1.0 (T13), 0.7 (T14) and 0.4 (T15) times of ETp(ETp was the accumulated of 20 cm pan evaporation during twice of the irrigation interval), were set for pot experiment and the irrigation time of each treatment was consistent with a cycle of 4~10 d, 3~7 d, 2~5 d and 4~10 d at seeding stage, squaring stage, blooming-boll forming stage and boll opening stage, respectively. The results were shown as follows, for plot experiment, seed yield, number of bolls per plant and single boll weight were maximum under T2, and the difference of seed yield was insignificant compared to T4, while WUE and IWUE decreased by 23.93% and 34.01%, respectively. For pipe experiment, the numbers of bolls per plant and seed yield were maximal under T7, where the seed yield decreased by 3.98% for T8 compared to CK while WUE and IWUE increased by 9.7% and 20.2%, respectively. For pot experiment, the numbers of bolls per plant and seed yield were maximal under T11, and seed yield increased by 9.7% and 30% compared to T12 and T13, respectively. This showed that moderate water stress was propitious to improve seed yield and WUE of intransplanted cotton following wheat harvest (lower limit 60%~65% FC, upper limit 80%~85% FC).