隔沟交替灌溉对棉花耗水、产量和品质的调控效应

在甘肃省石羊河流域下游民勤县干旱荒漠绿洲区研究了覆膜条件下隔沟交替灌溉(AFI)和常规沟灌(CFI)对棉花耗水、产量和品质的调控效应.结果表明,现蕾期和花期,AFI处理的棉花日耗水强度小于CFI处理;铃期和吐絮期,AFI处理棉花日耗水强度大于相同灌水定额的CFI处理.相同灌水定额条件下,AFI处理有利于籽棉产量和霜前花产量的提高,灌水定额为375 m3·hm-2和480 m3·hm-2的AFI处理,籽棉产量和WUE显著高于相同灌水定额的CFI处理.相同灌水定额条件下,AFI和CFI处理的衣分无显著性差异.2005年AFI处理的平均纤维长度比CFI处理长2.6mm,灌水定额为225m3·hm-2处理两者差异显著;2006年不同灌水方式下的纤维长度无显著差异,可能与降雨情况有关.在干旱缺水地区覆膜隔沟交替灌溉是一种有效的节水灌溉模式.在棉花品质不降低的情况下,有利于产量和水分利用效率的提高.

Effects of alternate furrow-irrigation on crop water consumption,yield and quality of cotton

A field experiment was carried out to study the effect of alternate furrow-irrigation (AFI) on water consumption characteristics, yield and quality of seed cotton in the oasis region of downstream Shiyang River Basin of Gansu Province. In the early stages of cotton growth (squaring to flowering stages), diurnal crop water consumption under conventional furrow-irrigation (CFI)is higher than in AFI. In the late stages (bolling to open-boll stages), diurnal crop water consumption under AFI is higher than in CFI. Under the same irrigation pattern, AFI improves yield of total seed cotton and seed cotton yield before frost. When irrigation is 375m³·hm^-2 and 480 m3·hm^-2, seed cotton yield and water use efficiency (WUE) under AFI are significantly higher than in CFI. In the two years, the difference in percent lint between AFI and CFI is insignificant. In 2005, average fiber length under AFI is 2.6 mm longer than in CFI, with a significant difference when irrigation is 225 m³·hm^-2. In 2006, no significant difference exists between AFI and CFI in fiber length. This can be attributed to different precipitation events in the two years. It is concluded that AFI is a feasible method of cotton cultivation in the oasis of Shiyang River Basin. With no reductions in fiber quality, AFI increases both seed cotton yield and water use efficiency.