覆盖方式对旱地不同熟性马铃薯产量及土壤水分的影响

Influence of different mulching patterns on soil moisture and yield of potato cultivars with different maturities in dryland farming

【目的】了解西北半干旱雨养条件下不同覆盖种植方式对马铃薯产量和水分的影响.【方法】以‘LK99’(早熟)、‘克新1号’(中熟)和‘青薯9号’(晚熟)为材料,设置秸秆带状覆盖(T_1)、地膜覆盖(T_2)和露地平作(CK)3种不同栽培方式,系统研究不同处理的土壤水分、产量和水分利用效率.【结果】与CK相比,T_1鲜薯产量增加13.7%～23.9%,干薯产量水分利用效率(WUE_D)提高34.3%～73.8%;T_2鲜薯产量增加24.7%～44.5%,WUE_D提高42.5%～63.8%.不同品种间鲜薯产量和WUE_D的最大增幅T_1处理均为早熟,T_2处理依次为早熟和中熟.覆盖显著提高单薯质量是增产的主要原因,早、中、晚熟马铃薯平均单薯质量比CK依次增加10.6、19.9和26.4 g.鲜薯产量与耗水量呈显著负相关(r=-0.671~*),与WUE_D呈极显著正相关(r=0.959^(**)).覆盖对各品种的不同时期和土层均具有增墒或降墒的双重效应,增墒作用更为显著,覆盖材料间增墒效果相似,但品种间差异较大,以晚熟品种覆盖土壤含水量较CK提高最显著(1.5%).【结论】秸秆带状覆盖和地膜覆盖均是半干旱雨养农区提高马铃薯产量和高效用水的技术,而秸秆带状覆盖栽培技术可减少污染,提高秸秆资源利用效率.

【Objective】In order to deeply understand the effects of different mulching patterns on soil moisture and tuber yield of potato cultivars with different maturities under semiarid rain-fed ecosystem.【Method】The cultivars‘LK99’(very early),‘Kexin 1’(medium-early)and‘Qingshu 9’(late)were selected to measure the soil moisture,tuber yield and water use efficiency under three cultivation patterns,including the flat-planting without mulching(CK),alternating the strips mulching with whole maize straw and bare plots with no ridges(T1);alternating large and small ridges mulching with black plastic film(T2).【Result】Compared with CK,T1 significantly increased fresh tuber yield by 13.7% to 23.9% and water use efficiency of drying tuber yield(WUE D)by 34.3% to 73.8% .T2 greatly improved fresh tuber yield by 24.7% to 44.5% and WUE D by 42.5% to 63.8% .The maximum increasing range of fresh tuber yield and WUE D were both the early maturing variety in T1,and early and medium-early maturing varieties in T2.Mulching treatments significantly increased single tuber weight,which was the main factor for tuber yield increasing.The average single tuber weight of early,medium-early and late potato cultivars with different maturities under mulching patterns significantly was increased by 10.6,19.9 and 26.4 g respectively compared with CK.The fresh tuber yield was negatively correlated with water consumption(r=-0.671*)and extremely positively correlated with WUE D(r=0.959**).Mulching had the dual effects on the increase or decrease of soil moisture in different soil layers at different growth stage,and the effect of increasing soil moisture was more significant.Both straw strips mulching and plastic mulching obtained similar soil moisture,but there were great differences among different varieties.The highest soil water content(1.5 percentage point higher than CK)occurred in late maturing cultivar under mulching.【Conclusion】Straw strips coverage and plastic mulching were proper techniques for improving potato yield and water use efficiency in semi-arid areas.Additionally,straw strips mulching could be applied as one of the effective farmland management practices to reduce pollution and enhance the utilization efficiency of straw resources.