陕西省不同年代旱地冬小麦光合与产量特征变化及其相互关系研究

为明确陕西省不同年代旱地冬小麦品种光合特征变化规律及其对产量的影响,选择曾在该省推广种植的20世纪40年代至21世纪初8个不同年代旱地冬小麦品种(蚂蚱麦,1940s;碧蚂1号,1950s;丰产3号,1960s;泰山1号,1970s;小偃6号,1980s;陕229,1990s;长武134,2000s;长旱58,2010s)为材料,设置正常供水和干旱胁迫两个水分处理,进行盆栽种植试验,对小麦不同生育期光合特征进行测定,并在收获期考种测产。结果表明,无论是干旱胁迫还是正常供水处理下,现代小麦品种(长武134和长旱158)花前旗叶净光合速率和单株叶面积都表现出显著优势,并与千粒重和产量呈显著正相关;但品种间花后光合特征差异减小,这对于现代小麦产量的提升可能产生了一定的限制作用;不同生育时期和不同水分处理下,旗叶蒸腾速率与种植年代之间相关性并不一致;干旱胁迫条件下,孕穗期和花后3d的旗叶水分利用效率都随品种更替呈明显上升的趋势;现代小麦品种在干旱处理下旗叶净光合速率等光合特征、千粒重等产量因素的优势受到影响,最终导致其产量增幅下降。未来应进一步提升现代小麦的光合优势,尤其是花前叶片净光合速率及叶面积的优势,并进一步提高千粒重,这将会是陕西省小麦节水高产和抗旱稳产的重要手段。

Photosynthetic Traits,Yield and Their Relations of Dryland Winter Wheat Cultivars in Different Decades of Shaanxi Province

Eight dry-land winter wheat cultivars (Triticum aestivum L.),representative of those cultivars widely cultivated during the 1940s to the 2010s in Shaanxi province of China,were selected and grown in pots during the growing season of 2010-2011 for irrigation and drought treatments.,the morphological and photosynthetic traits associated with yield progress were investigated. The results showed that modern cultivars presented significant advantage on flag leaf photosynthetic rate and leaf area per plant at booting stage under both irrigation and drought treatments,which was beneficial for increasing thousand grain weight and yield; the advantage on photosynthetic traits of modern cultivars were decreased after flowering,which might limit the yield increase; the correlation between transpiration rate and planting decades were not consistent at different stages or different water treatments; water use efficiency of flag leaf of wheat cultivars at both booting stage and 3 days after flowering was increased significantly along with time released under drought treatments; yield increase of modern cultivars under drought treatment was limited directly by the decrease of photosynthetic and morphological traits. Further improvement on photosynthetic traits,especially photosynthetic rate and leaf area before flowering to enhance the thousand grain weight,will be available ways to achieve the target of stable yield for wheat cultivars with drought resistance and high yield.