秸秆覆盖和土壤水分互作对夏玉米水分利用效率及产量的影响

Effect of straw mulches and water supply interactionon on yield and water use efficiency of summer maize

为阐明秸秆覆盖和土壤水分互作对夏玉米水分利用的影响,采用两因素裂区试验设计,通过防雨棚测坑试验,研究了秸秆覆盖和水分调控对夏玉米产量和水分利用的影响.结果表明,秸秆覆盖可显著降低夏玉米不同生育时期棵间蒸发量(Ed),在夏玉米生育前期的表现尤为明显.夏玉米全生育期耗水量(ET)、灌浆期光合参数、单叶水分利用效率(WUEL)、水分利用效率(WUE)和产量受到秸秆覆盖和土壤水分调控的显著影响,且光合参数(除净光合速率Pn外)和产量受到秸秆覆盖和水分调控的交互作用的显著影响,秸秆覆盖较不覆盖能显著减少ET、提高WUE和产量,ET和产量随着土壤水分调控水平的提高而提高,WUE随着土壤水分调控水平的提高而降低.从低水分到高水分秸秆覆盖较不覆盖WUE增幅为35.32%,33.74%,51.88%和29.69%,产量增幅为7.61%,8.94%,18.29%,6.96%.秸秆覆盖条件下土壤70%田间持水量水分处理,ET较少,产量和水分利用效率较高且增幅最大.

A split-plot experiment has been conducted to illustrate the effect of straw mulches and soil moisture on yield and water use efficiency of summer maize grown in no-weighting lysimeters under a rain-shelter. Two factors were applied in the experiment with straw returning regime as the main factor and water supply as the subsidiary factor. The results showed straw returning could significantly de- crease soil evaporation of summer maize of different stage, especially in the early stage. Straw returning and water supply had significant effect on water consumption, photosynthetic parameter, water use effi- ciency of leaf （WUEL） , water use efficiency （WUE） and yield in the whole period （ET）. Interaction of straw returning regime and water supply had a significant effect on photosynthetic parameter （ except net photosynthetic rate and yield. Straw returning could decrease ET and increase the water use effi- ciency （WUE） and yield. Yield increased along with increased water supply, while WUE decreasedalong with increased water supply. WUE of straw returning with each water supply increased by 35.32% , 33.74% , 51.88% and 29.69% respectively compared with non-straw returning, and yield of maize increased by 7.61% , 8.94% , 18.29% and 6.96% , respectively. To sum up, straw retur- ning with 70% field soil water capacity supply showed the best performance on ET, yield and WUE to- gether. It could achieve the result of water-saving and high yield.