摘要： 通过管栽和盆栽试验研究了返青期根修剪对冬小麦地上和地下部分生长发育、水分利用效率及产量形成的影响。设置3个根修剪处理：返青期小切根、返青期大切根和未切根对照（CK）。结果表明，根修剪可降低叶片SPAD值，尤其大切根处理生育后期叶片持绿性较差。切根对小麦单株分蘖有一定程度的抑制作用，但小切根可促进有效蘖的生长，使成熟期单株分蘖较高，但大切根处理分蘖及成熟期分蘖均较低。小切根通过对根系的适当调控，使0~140 cm根系冗余量减少，根冠比降低，但在水分充足的条件下促进浅层根系（0~60 cm）的生长，抑制了深层根系的生长。小切根可促进地上部生长，使叶面积和地上部干质量增加，因而使单株粒重增加；大切根处理由于根系过度修剪，根干质量和地上部干质量均降低，因而单株粒重明显减少。适度的根修剪（小切剪）耗水量、产量和水分利用效率（WUE）均提高，尤其是在限水条件下适度根修剪可使产量和WUE增幅更大，但大切根处理由于粒重较低，尽管耗水量减小，但WUE大幅降低。

关键词: 小麦, 切根, 产量, 水分利用效率

Abstract: Through tube and pot cultivation experiment,the effect of root pruning in regreening stage on growth development,water use efficiency and yield formation of winter wheat were researched.Three root pruning in regreening stage were set in 2013-2014 and 2014-2015,included small root pruning,large root pruning and no root pruning (CK).The result showed that leaf SPAD values was reduced after root pruning,for large root pruning treatment,its leaf SPAD value decreased rapidly at late growth stage.Tiller per plant was restrained when the root was pruned,but the growth of effective tiller was promoted when the root was pruned mild,thus the tiller per plant was increased significantly,while tillering ability and effective tiller of mature period was low when the root was pruned severe.Root weight of 0-140 cm was reduced when the root was pruned mild,and root and shoot ratio decreased,the main reason for the decrease of root weight was that the deep root weight was reduced.The leaf area and dry matter weight of shoot was increased when the root was pruned mild,thus the grain weight per plant was also increased corresponding.Due to excessive root pruning for large root pruning treatment,its root and shoot dry weight were decreased,and the grain weight per plant was significantly reduced.Water consumption,grain yield and water use efficiency were increased obviously when the root was pruned mild,especially the trend was more obvious under limiting water condition,and for large root pruning treatment,although the water consumption was reduced,but grain weight was decreased also,so water use efficiency was significantly reduced.

Key words: Wheat, Root pruning, Grain yield, Water use efficiency

中图分类号: 

• S512.01