半干旱区全膜覆土穴播对春小麦耗水特征和产量的影响

Effects of full plastic-film mulching with bunch planting on water consumptioncharacteristics and grain yield of spring wheat in semi-arid region

为研究甘肃半干旱地区全膜覆土穴播小麦的耗水特征及其对产量的影响,以春小麦陇春27号为材料,于2012-2014年,通过3年大田定位试验,设全膜覆土穴播(PMS)和露地穴播(CK)2个处理,分析了不同生育阶段耗水量、耗水模系数、耗水速率、生长速率、耗水效率和水分利用效率等指标。结果表明,PMS处理0～300 cm土层土壤贮水量高于CK,苗期、拔节期和灌浆期分别增加了15.6～34.1 mm、20.7～22.1 mm和15.1～42.1 mm。在播种-拔节期,PMS处理在2013、2014年的耗水模系数和耗水速率较CK分别增加了16.9%、10.5%和20.0%、5.8%,灌浆期分别降低了28.2%、10.6%和26.3%、14.4%。在2012-2014年PMS处理的生长速率较CK分别提高了87.0%～153.7%、42.8%～366.1%、87.4%～133.0%;耗水效率分别提高了73.3%～200.2%、93.8%～288.2%、77.1%～155.5%,均差异显著。PMS处理的株高、单株重、小穗数、穗粒数、穗粒重和千粒重均显著高于CK,产量增加了35.4%～61.9%,水分利用效率(WUE)提高了44.6%～63.3%。表明全膜覆土穴播能显著调节春小麦在不同降水年型的耗水进程和耗水特性,提高地上部生物量、生长速率和耗水效率,在全生育期耗水量无显著增加的条件下,显著提高产量和WUE。

The study on spring wheat water consumption and its effects on grain yield of spring wheat are helpful to understand the mechanism of grain yield increase of soil-plastic mulching technology in semiarid region of northwest Loess Plateau.This is also necessary to explore the technology,which could improve the water use efficiency and yield in the future.The spring wheat(Triticum aestivum,longchun 27)was selected as test material and a field experiment was conducted from 2012 to 2014 on northwest Loess Plateau(104°36′E,35°35′N).The two treatments were:whole field soil with plastic mulching and bunching seeded(PMS),unmulched field and bunching seeded(CK).The seasonal soil water content,aboveground biomass,yield,and its components were measured;the periodical water consumption,water consumption modulus coefficient,water consumption rate,plant growth rate,water consumption efficiency and grain water use efficiency(WUE)had been calculated.The soil water storage in 0~300 cm profile of PMS was higher than that in CK,increased by 15.6~34.1 mm in seedling stage,20.7~22.1 mm in jointing stage and 15.1~42.1 mm in filling stage from 2012 to 2014.From sowing to jointing stages,the water consumption modulus coefficient and water consumption intensity of PMS were higher than that with CK by 16.9% ,10.5% ,and 20.0% ,5.8% ,from filling to maturity,it was lower than that with CK by 28.2% ,10.6% ,and 26.3% ,14.4% in 2013 and 2014,respectively.The growth rate was increased by 87.0% ~153.7% ,42.8% ~366.1% ,87.4% ~133.0% and the water consumption efficiency were increased by 73.3% ~200.2% ,93.8% ~288.2% ,77.1% ~155.5% ,respectively.The plant height,plant weight,spike lets,grain number,grain weight per spike,1000-grain weight of PMS were significantly higher than that with CK,resulted in the increment of 35.4% ~61.9% for grain yield,and 44.6% ~63.3% for the water use efficiency without significantly increase in evapotranspiration.Consequently,soil-plastic mulching and bunching seeding regulated water consumption process and characteristics of spring wheat in different precipitation years significantly,increased aboveground biomass growth rate and water consumption efficiency,resulted in the significant improvement in grain yield and WUE,where without remarkable increase in evapotranspiration in whole growth season.