不同耕作方式对旱作冬小麦旗叶衰老和籽粒产量的影响

Effects of tillage pattern on the flag leaf senescence and grain yield of winter wheat under dry farming

在旱作条件下研究了一次深翻、免耕、深松和传统耕作4种耕作方式对冬小麦花后旗叶衰老、小麦籽粒产量及土壤水分和养分状况的影响.结果表明:免耕和深松提高了小麦旗叶SOD和POD活性及可溶性蛋白和叶绿素含量,降低了MDA和O2.-含量,延缓了小麦叶片的衰老进程;同时,免耕、深松在开花期和灌浆期0～40cm土层土壤水分含量分别比传统耕作提高了4.13%、6.23%和5.50%、9.27%,土壤碱解氮、速效磷和速效钾含量均显著高于传统耕作.一次深翻0～40cm土层土壤水分含量低于传统耕作,土壤养分含量高于传统耕作,但两处理间差异不显著.与传统耕作相比,免耕和深松花后干物质生产量分别提高4.34%和4.76%,花后干物质转运率分别提高15.56%和13.51%,产量分别提高10.22%和9.26%.免耕和深松为冬小麦花后生长发育提供了良好的环境,延缓了小麦叶片衰老,促进了花后干物质积累及干物质向籽粒的转运,从而使籽粒产量显著提高,是旱作麦区适宜的耕作方式.

A field experiment deep plowing once, no-tillage, was conducted to study the effects of different tillage subsoiling, and conventional tillage , on the flag leaf patterns, t. e. , senescence and grain yield of winter wheat, as well as the soil moisture and nutrient status under dry farming. Notillage and subsoiling increased the SOD and POD activities and the chlorophyll and soluble protein contents, decreased the MDA and O2 contents, and postponed the senescence of flag leaf. Under non-tillage and subsoiling, the moisture content in 0-40 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 0-40 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.