关键词: 干旱, 内源激素, 气孔导度, 棉花, 膜下滴灌

Abstract: A field experiment was conducted to study the effects of different tillage patterns, i.e., deep plowing once, no-tillage, subsoiling, and conventional tillage, on the flag leaf senescence and grain yield of winter wheat, as well as the soil moisture and nutrient status under dry farming. No-tillage and subsoiling increased the SOD and POD activities and the chlorophyll and soluble protein contents, decreased the MDA and O〖SX（B-*3〗-〖〗·〖SX）〗2 contents, and postponed the senescence of flag leaf. Under non-tillage and subsoiling, the moisture content in 0〖KG-*2〗-〖KG-*7〗40 cm soil layer at anthesis and grain-filling stages was decreased by 413% and 623% and by 550% and 927%, respectively, and the contents of alkali-hydrolysable N, available P, and available K in this soil layer also increased significantly, compared with those under conventional tillage. Deep plowing once decreased the moisture content and increased the nutrients contents in 0〖KG-*2〗-〖KG-*7〗40 cm soil layer, but the decrement and increment were not significant. The post-anthesis biomass, post-anthesis dry matter translocation rate, and grain yield under no-tillage and subsoiling were 434% and 476%, 1556% and 1351%, and 1022% and 926% higher than those under conventional tillage, respectively. It could be concluded that no-tillage and subsoiling provided better soil conditions for the post-anthesis growth of winter wheat, under which, the flag leaf senescence postponed, post-anthesis dry matter accumulation and translocation accelerated, and grain yield increased significantly, being the feasible tillage practices in dry farming winter wheat areas.

Key words: drought stress, endogenous hormone, stomatal conductance, cotton, drip irrigation with mulch.