秸秆带状沟覆垄播对旱地马铃薯产量和水分利用效率的影响

为探明西北半干旱雨养农业区马铃薯(SolanumtuberosumL.)生产中沟垄不同覆盖种植方式的增产效果和水分利用特点,在2016年和2017年设置了大田试验,包括秸秆带状沟覆宽垄种植、秸秆带状沟覆微垄种植、全覆膜沟垄种植和露地平作4个处理。结果表明,在干旱年份(2016年),沟垄覆盖种植可显著降低马铃薯全生育期耗水量6.1%～13.2%,平均提高块茎形成期1.2～1.8 m土层含水量7.6%,全覆膜沟垄作可显著提高淀粉积累期0～0.2 m土壤含水量30.3%。在平水年份(2017年),除全覆膜沟垄种植显著降低马铃薯全生育期耗水量22.2%外,其余处理与露地平作无显著差异;沟垄覆盖种植0～2m土壤含水量在马铃薯块茎形成期、块茎膨大期和淀粉积累期分别平均比露地平作高8.7%、13.0%和13.1%。与露地平作相比, 2个生长季沟垄覆盖种植可使马铃薯全生育期0～2 m土壤平均贮水量提高5.4%～15.5%,单株生物量增加12.8%～147.4%,成熟期株高增加21.1～39.7cm,进而马铃薯增产51.6%～88.2%,水分利用效率提高68.2%～111.7%。以玉米秸秆带状沟覆微垄种植增产增效最显著,2年平均产量、水分利用效率和纯经济收益分别较露地平作提高87.8%、97.5%和254.2%。因此,玉米秸秆带状沟覆微垄种植能显著提高马铃薯产量和水分利用效率。此外,与全覆膜沟垄种植相比,秸秆带状沟覆微垄种植具有操作简单、无污染、投入产出比高等优点,适宜在西北半干旱区马铃薯生产中应用。

Effects of straw strip mulching on furrows and planting in ridges on water use efficiency and tuber yield in dryland potato

Field experiments were conducted to study the effects of different mulching materials and ridge-furrow widths on potato (Solanum tuberosum L.) growth, tuber yield, soil moisture and water use efficiency in a semiarid rain-fed ecosystem in northwest China in 2016 and 2017. Four treatments were performed: (1) alternating narrow furrows and wide ridges with corn straw strip mulching only on narrow furrows and planting in the wide ridges (RFWN); (2) alternating micro-ridge-furrows with corn straw strip mulching only on furrows and planting in the ridges (RFN); (3) alternating small and large ridges full mulching with black plastic film and planting in the large ridges (RFB), and (4) traditional-flat planting without mulching (CK). Compared with CK, mulching treatments significantly decreased total evapotranspiration by 6.1%-13.2%, increased average soil water content (1.2-1.8 m depth) by 7.6% at tuber initiation stage, and RFB treatment significantly increased soil water content (0-0.2 m) by 30.3% at starch accumulation stage in the dry year of 2016. In the normal precipitation year of 2017, the total evapotranspiration in RFB was 22.2% lower than that in CK, and there was no significant difference in total evapotranspiration observed among the RFWN, RFN and CK treatments. The average soil water content (0-2 m depth) in mulching treatments was 8.7%, 13.0%, and 13.1% higher than that in CK, respectively, at tuber initiation, tuber bulking and starch accumulation stage in 2017. Compared with CK, mulching treatments significantly increased soil water storage (0-2 m), weight of dry matter per plant and final plant height by 5.4%-15.5%, 12.8%-147.4%, and 21.1-39.7 cm, respectively, and thus enhanced tuber yield and water use efficiency by 51.6%-88.2% and 68.2%-111.7% in both years, respectively. The tuber yield, water use efficiency and net income for RFN treatment was the highest increasing on average by 87.8%, 97.5%, and 254.2%, respectively, in both years. In addition, RFN had the advantages of simple operation, the environmentally friendly and the highest input/output ratio compared with the treatment of plastic film mulching. Hence, RFN is the best cultivation model for dryland potato.