加气对西北旱区膜下滴灌棉花光合及水分利用效率的影响

Effects of aeration on photosynthesis and water use efficiency of cotton under mulched drip irrigation in arid area of Northwest China

为探明西北旱区滴灌棉花适宜的加气灌溉模式,试验以不加气灌溉为对照(CK),设置5个加气灌溉处理:苗期加气(AS)、蕾期加气(AB)、花铃期加气(AF)、蕾期加气+花铃期加气(ABF)、苗期加气+蕾期加气+花铃期加气(AW);研究了不同生育期加气灌溉对西北旱区棉花光合作用及水分利用效率的影响.结果表明,与CK相比,所有加气处理的光合特性及地上部生物量都显著提高,其中处理AW较CK的净光合速率显著增加22.68%,蒸腾速率显著增加41.19%,气孔导度显著增加33.42%,胞间CO 2浓度显著降低16.22%;花铃期加气灌溉使西北旱区棉花地上部茎、叶、蕾/铃干物质累积量分别显著增加29.26%,11.15%和33.41%.不同生育期加气灌溉下,棉花光合特性、地上部生物量以及产量最优的处理为AW和AF,且差异不具有统计学意义;但是处理AF的水分利用效率最高,为1.51 kg/m 3,显著高于处理AW.因此,从高效节水增产的角度考虑,在棉花花铃期进行加气(AF)可作为西北旱区膜下滴灌棉花的最佳加气灌溉模式.

In order to find out the suitable aerated irrigation mode for drip irrigation cotton in arid area of Northwest China,five aerated irrigation treatments were set up with non-aerated irrigation as control(CK):aerated irrigation at seedling stage(AS),aerated irrigation at budding stage(AB),aerated irrigation at flowering and boll stage(AF),aerated irrigation at budding stage+aerated irrigation at flowering and boll stage(ABF),and aerated irrigation at seedling stage+aerated irrigation at budding stage+aerated irrigation at flowering and boll stage(AW).The effect of aerated irrigation at different growth stages on the photosynthesis and water use efficiency of cotton in arid areas of Northwest China was studied.The results show that compared with CK,the photosynthetic characteristics and aboveground biomass of all aerated treatments are significantly increased.Among them,the net photosynthetic rate of aerated treatment is significantly increased by 22.68%,the transpiration rate is significantly increased by 41.19%,the stomatal conductance is significantly increased by 33.42%,and the intercellular CO 2 concentration is significantly decreased by 16.22%,respectively.Aerated irrigation at the flowering and boll stage significantly increases the dry matter accumulation of stems,leaves and buds/bolls by 29.26%,11.15%and 33.41%,respectively.Under aerated irrigation at different growth stages,the optimal treatments for cotton photosynthetic characteristics,aboveground biomass and yield are AW and AF,and there is no significant difference.However,the water use efficiency of AF treatment is the highest,which is 1.51 kg/m 3,significantly higher than that of AW treatment.Therefore,from the perspective of efficient water-saving and yield-increasing,aerated irrigation at the flowering and boll stage(AF)of cotton can be used as the best aeration irrigation mode for cotton under mulched drip irrigation in arid areas of Northwest China.