Effects of root pruning on the growth and water use efficiency of winter wheat
Effects of root pruning on the growth and water use efficiency of winter wheat
复制标题
断根对冬小麦生长及水分利用效率的影响
DOI：
10.1007/s10725-008-9340-1
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Zhanbin Huang
中科院分区：
文献类型：
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作者：
Shou;Fengmin Li;Bingcheng Xu;Zhanbin Huang
采用盆栽试验研究了拔节期断根对冬小麦生长和水分利用效率的影响。结果表明，小麦气孔导度（g）和蒸腾速率（E）对根系修剪非常敏感。根修剪后，他们迅速下降，但恢复到修剪前的值处理后15天。在水分充足的条件下，断根后的叶片水势与对照无显著差异。中度干旱胁迫下，断根后3 d，断根植株的叶片数较对照显著下降。15天后，断根植株的叶片与对照相似。在不同土壤水分条件下，断根后3-7天，断根植株的净同化率（A）低于对照，但在断根后15天与对照相近。在开花期（断根后50天），断根植株表现出显着高于对照。孕穗期剪根处理的单株分蘖叶面积和分蘖数显著低于对照，表明剪根处理抑制了植株生长前期的生长，而开花期剪根处理的单株茎叶面积与对照相近。在两种土壤水分条件下，单作条件下，断根处理与对照的籽粒产量差异不显著。在与对照植物的混合物中，根修剪植物的生产力较低，相对产量（分别为0.92和0.78）与对照（分别为1.13和1.19）相比，这表明修剪植物失去了一定的竞争能力，并表现出较低的能力，以获得和利用相同的资源与对照植物的混合物。在整个生育期内，剪根处理显著降低了小麦的耗水量（在充分供水条件下降低了10%，在中度干旱胁迫下降低了16%）（P< 0.05），但剪根处理的籽粒产量与对照差异不显著。因此，与对照相比，断根小麦具有较高的WUE。因此，在干旱半干旱地区，通过早期断根降低耗水量是提高水分利用效率的有效途径。
A pot experiment was conducted to study the effects of root pruning at the stem elongation stage on the growth and water use efficiency (WUE) of winter wheat (Triticum aestivum). The results showed that stomatal conductance (g) and transpiration (E) of wheat were very sensitive to root pruning. After root pruning, they declined rapidly and but returned to pre-pruning values 15 days after treatment. Under well-watered conditions, there was no significant difference in leaf water potential (ψleaf) between root pruned and control plants after root pruning. Under moderate drought stress, ψleafof root pruned plants declined significantly compared to the control 3 days after root pruning. After 15 days, ψleafof root pruned plants was similar to the controls. Under different soil moisture levels, net assimilation rate (A) of root pruned plants was lower than controls 3–7 days after root pruning, but was similar to the controls 15 days after pruning. At anthesis (50 days after root pruning), root pruned plants showed significantly higherAcompared with the control. Leaf area per tiller and tiller number of root pruning plants was significant lower than the control at booting stage, which showed that root pruning restrained the growth of plants in the early growing stage, but leaf area per stem, of root pruned plants, was similar to the control at anthesis. Under both soil moisture levels, there was no significant difference in grain yield between root pruned and the control plants in the monoculture. In mixture with the control plants, the root pruned plants was less productive and had a lower relative yield (0.92 and 0.78, respectively) compared with the control (1.13 and 1.19, respectively), which suggested that the pruned plants lost some of its competing ability and showed a lower ability to acquire and use the same resources in the mixture compared with the control plant. Over the whole growing cycle, root pruning reduced water consumption (by 10% under well-watered conditions and 16% under moderate drought stress) of wheat significantly compared to the control (P< 0.05), and but there was no significant difference in grain yield between root pruned and control plants. Therefore root pruned wheat had a higher WUE with respect to grain yield compared with the controls. In conclusion, lowering water consumption by root pruning in the early growing stage is an effective way to improve water use efficiency in arid and semi arid areas.