覆盖方式对旱地马铃薯阶段耗水量特征和产量的影响

为明确不同覆盖方式对旱地马铃薯田土壤耗水、耗水规律、水分利用效率、产量及产量形成的影响,在陇中半干旱农区设置了玉米秸秆带状双行覆盖(SSM2)、玉米秸秆带状单行覆盖(SSM1)、玉米秸秆全覆盖(SFM)、地膜春覆盖(PMS)和地膜秋覆盖(PMA)5种覆盖方式,以传统露地平作为对照(CK)。结果表明:2年试验中,玉米秸秆带状覆盖和地膜覆盖处理土壤贮水消耗量较CK分别增加13.5,14.8 mm。玉米秸秆带状覆盖能显著提高降水对马铃薯耗水贡献率,不同降雨年型内均以SSM2处理贡献率最高,2年分别为95.6%和94.3%。于CK相比,覆盖处理均降低了生育前期(播种-块茎形成期)耗水量,地膜覆盖显著增加了生育中期(块茎形成期-淀粉积累期)耗水量,玉米秸秆带状覆盖显著增加了生育后期(淀粉积累期-收获期)的耗水量。玉米秸秆带状覆盖和地膜覆盖分别能使马铃薯干薯产量增加27.9%和24.2%,干薯水分利用效率提高23.1%和19.3%。综上可知,玉米秸秆带状覆盖处理能显著增加马铃薯生育时期内农田土壤贮水消耗量,并改善马铃薯生育前期和生育后期耗水,减少旱地马铃薯农田无效耗水,能显著提高马铃薯干薯产量和水分利用效率。

Effects of Mulching Methods on Water Consumption and Yield of Potato in Dryland Farming

In order to determine the effects of different mulching methods on soil water depletion, water consumption patterns, water use efficiency, yield and yield formation in dryland potato fields, five mulching methods, including whole maize straw strip double row mulching (SSM2), whole maize straw strip single row mulching (SSM1), full mulching of maize straw (SFM), plastic film spring mulching (PMS) and plastic film autumn mulching (PMA), were set up in the semi-arid agricultural region of Longzhong, with the traditional bare land as the control (CK). The results showed that compared with CK, Soil water consumption increased by 13.5 and 14.8 mm for the whole maize straw strip mulching and plastic film mulching. The whole maize straw strip mulching could significantly increase the contribution of precipitation to potato water consumption, the highest contribution was found in SSM2 in different rainfall year types, 95.6% and 94.3% respectively in two years. Compared with CK, all mulching treatments reduced water consumption in the early growth stage (from sowing to tuber initiation), the whole maize straw strip mulching increased water consumption in the later growth stage (from starch accumulation to harvest), and the plastic film mulching increased water consumption in the middle growth stage (from tuber initiation to starch accumulation). The whole maize straw strip mulching and plastic film mulching increased drying tuber yield of potatoes by 27.9% and 24.2%, and water use efficiency increased by 23.1% and 19.3%. In conclusion, it can be seen that the whole maize straw strip mulching could significantly increase the soil water storage consumption during the full growth stage of potato, and improve the water consumption in the early and later growth stages, reduce the inefficient water consumption in dryland potato farms, and significantly improve drying tuber yield and water use efficiency of potato.