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为探明北疆地区不同抗旱性滴灌春小麦品种根系形态及内源激素在开花期干旱后复水过程中的变化特征及其与生物量的关系，以春小麦耐旱性强品种新春6号和耐旱性弱品种新春22号为材料，在土柱栽培下设置常规灌溉（CK）、开花期轻度干旱和中度干旱3种水分条件，分析了干旱胁迫后复水条件下不同耐旱性小麦品种根系形态特征、渗透调节物质及内源激素和生物量的差异。结果表明，两个品种的根长密度（RLD）、根体积密度（RVD）、根表面积密度（RSAD）、可溶性糖（SS）含量、脯氨酸（Pro）含量、生长素（IAA）含量、赤霉素（GA₃）含量、玉米素（ZT）含量、地上部干物质积累量（SDM）以及产量均在干旱复水后随时间呈先增后降趋势，以轻度干旱后复水条件下表现最佳。两个品种比较，在轻度干旱后复水条件下新春6号的RLD、RVD、RSAD、SS含量、Pro含量、IAA含量、GA₃含量、ZT含量、ABA含量、SDM及产量较新春22号平均高出3.38%、4.30%、4.29%、21.84%、10.81%、5.99%、10.02%、16.05%、3.13%、6.86%和3.47%。经相关分析，两个品种于各处理下的RLD、RVD、RSAD、SS含量、Pro含量与IAA含量、GA₃含量和ZT含量间均呈显著正相关，与ABA含量呈显著负相关。综上所述，较优的根系生长及生理代谢是春小麦具有较高抗旱性的原因；轻度干旱后复水可调节滴灌春小麦根系渗透调节物质和内源激素含量变化，进而优化根系形态，促进干物质向穗部转运及产量形成，可作为新疆滴灌春小麦灌溉模式。

英文摘要:

To in vestigate the effects of rehydration on root morphology and endogenous hormones of different drought tolerant spring wheat varieties and its relationship with biomass in Northern Xinjiang after drought at anthesis stage, a drought tolerant variety Xinchun 6 and a drought sensitive variety Xinchun 22 were used as materials. Three treatments including conventional irrigation (CK), mild drought (T1) and moderate drought (T2) at anthesis stage were set up under soil column cultivation, and the differences of root morphological characteristics, osmoregulatory substances, endogenous hormones and biomass of different drought tolerant wheat varieties under different conditions of rehydration after drought stress were analyzed. The results showed that the root length density (RLD), root volume density (RVD), root surface area density (RSAD), soluble sugar (SS)content, proline (Pro)content, auxin (IAA)content, gibberellin (GA₃)content, zeatin (ZT) content, shoot dry matter accumulation (SDM), and yield of the two varieties increased first and then decreased with time after rehydration after drought, with the best performance under the conditions of rehydration after mild drought. Compared with Xinchun 22, the RLD, RVD, RSAD, SS content, Pro content, IAA content, GA₃ content, ZT content, ABA content, SDM, and yield of Xinchun 6 were 3.38%, 4.30%, 4.29%, 21.84%, 10.81%, 5.99%, 10.02%, 16.05%, 3.13%, 6.86% and 3.47% higher than those of Xinchun 22 under the conditions of rehydration after mild drought. Correlation analysis showed that the RLD, RVD, RSAD, SS content, Pro content and IAA content, GA₃ content, and ZT content of the two varieties under each treatment were significantly positively correlated, and significantly negatively correlated with ABA content. To sum up, better root growth and physiological metabolism are the reasons why spring wheat has higher drought resistance; rehydration after mild drought can adjust the changes of osmotic regulating substances and endogenous hormone contents in spring wheat roots under drip irrigation, thus optimizing the root morphology, promoting the translocation of dry matter to the ear and yield formation, which can be used as the irrigation model for spring wheat under drip irrigation in Xinjiang.

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