增强UV-B辐射和干旱对不同品种春小麦生长、产量和生物量的影响

 【目的】通过研究增强UV-B辐射和干旱胁迫对不同品种春小麦生长、产量和生物量的影响,为筛选高产、抗旱、抗UV-B辐射春小麦新品种提供依据。【方法】设置干旱、增强UV-B辐射以及二者复合处理处理西北干旱区三个不同的主栽春小麦品种,检测和分析旗叶面积、叶片厚度、叶面积指数、生物量、根冠比、产量和收获指数等生理指标。【结果】增强UV-B辐射可抑制春小麦分蘖,而适度干旱胁迫可促进春小麦分蘖;增强UV-B辐射和干旱胁迫条件下,定西-24、陇春-8139、和尚头生物量分别降低22%,21%和15%,,平均降低20%;复合作用对产量和生物量的影响与增强UV-B辐射和干旱胁迫分别处理相比,没有明显的减少;干旱胁迫较增强UV-B辐射和二者的复合作用对收获指数和产量的负面影响稍小;干旱胁迫使和尚头和定西-24收获指数增加10%,陇春-8139增加23%;而增强UV-B辐射下和尚头的收获指数下降10%,定西-24和陇春-8139的收获指数均提高10%。说明不同品种春小麦在干旱胁迫、增强UV-B辐射以及二者复合作用下,光合产物向生殖器官的分配比例不同。【结论】春小麦对干旱和增强UV-B辐射胁迫的响应存在品种间的差异性;3个品种对干旱胁迫和增强UV-B辐射的响应趋势基本一致; 干旱胁迫和增强UV-B辐射对3个品种生长都具有抑制效应,但品种间存在一定的敏感性差异。在干旱胁迫和增强UV-B辐射作用下,陇春-8139较定西-24、和尚头分蘖少,但千粒重、收获指数和产量最高。因此,陇春-8139在抗旱、抗UV-B辐射和增产方面比其他2个品种具有更大的优势。

Effects of Enhanced UV-B Irradiance and Drought Stress on the Growth, Production, and Biomass of Spring Wheat

【Objective】 The effects of enhanced UV-B radiation and drought stress on growth, production, and biomass of three spring wheat varieties were studied to provide a basis for breeding spring wheat varieties of high yield and tolerance to drought and anti UV-B radiation. 【Method】 Drought, enhanced UV-B radiation, and interaction between drought and enhanced UV-B radiation were set to analyze the morphologic index such as flag leaf area, leaf thickness, leaf area index, biomass, root to shoot ratio, and production harvest index, and other biological indicators of three spring wheat cultivars in northwestern China as well. 【Result】 The results showed that enhanced UV-B radiation restrained the node-tillering, resulting in decreased number of tillering nodes, and that moderate drought increased the number of tillering nodes. Under the enhanced UV-B radiation and drought, the biomass of Dingxi-24, Longchun-8139 and Heshangtou reduced by 22%, 21% and 15%, respectively, the average reduction of biomass was 20%. Drought had a less adverse effect on harvest index and yield than enhanced Ultraviolet-B radiation and the interaction between them did. Drought stress increased the harvest index of Heshangtou and Dingxi-24 by 10%, Longchun-8139 by 23%. In contrast, enhanced ultraviolet radiation-B decreased the harvest index of Heshangtou by 10%, and it increased the harvest index of Dingxi-24 and Longchun-8139 by 10%. This indicated that different species allocated inequable proportion of biomass to procreation growth under enhanced ultraviolet-B radiation, drought and the interaction between them. 【Conclusion】 There is a difference among varieties of spring wheat under enhanced ultraviolet-B radiation and drought. Response trend of the three species to enhanced ultraviolet-B radiation and drought is by and large accordant. Drought and enhanced ultraviolet-B radiation had a restraining effect on the three species, but sensible difference amongst species. Longchun-8139 showed a lower number of tillering nodes, highest harvest index and yield in contrast to Heshangtou and Dingxi-24 under enhanced ultraviolet-B radiation and drought. Therefore, Longchun-8139 had more advantages over Heshangtou and Dingxi-24 under enhanced ultraviolet-B radiation and drought.