灌浆期断根对小麦产量及相关生理性状的影响

Effect of Pruning Root in Grain Filling Stage on Yield and Physiological Characteristic of Winter Wheat

为给小麦生长发育进程中的根系调控提供依据,以小麦品种山农9-1为试验材料,研究了不同土层断根对小麦生育后期生理性状及产量的影响。结果表明,断根处理使小麦根系活力降低,叶片光合能力下降,膜脂过氧化加剧,加速了小麦的衰老,明显降低了产量,表现为断根越浅,影响越大。断根后浇水对产量有弥补作用;地表向下20 cm处断根,产量降低35.9%-43.4%,即该层根系对后期产量形成的相对作用为56.6%-64.1%,而20-40、40-80、80-100 cm以及100 cm以下根系对产量的相对作用为10.0%-12.8%、3.3%-7.9%、5.5%-6.5%和14.3%-19.0%,即100 cm以下深层根和20 cm以上的表层根共同构成两头大中间低的根效分布。100 cm以下的根系对产量的相对作用则表现为不浇水相对较大,说明1 m以下的种子根群,在小麦生育后期遭遇干旱情况下对籽粒形成更为重要。

To facility the regulation of roots in wheat production, the effects of root pruning was studied in grain filling stage on wheat. Including the changes of chlorophyll content in the flag leaf and root activity, POD activity in root. The results showed that（1）while root of wheat was pruned in the first period of filling stage from different depth, yield of wheat and related physiological traits decreased significantly. Shallower root pruned, more the wheat plant was affected. Water treatment after root pruning may compensate to yield. （2）Yield of wheat dropped 35.9%-43.4% by pruning root from the ground surface to 20 cm depth, from the filling stage to maturity, The contribution of 0 to 20 cm depth roots to yield is 56.6%-64.1%. （3） The contribution of roots in depth of 20-40 cm, 40- 80 cm, 80-100 cm and 100 cm, to yield is 10.0%-12.8%. 3.3%-7.9%,5.5%-6.5% and 14.3% -19.0%, respectively. The roots deeper than 100 cm and that of lower than 20 cm constitute the two major roots. （4）The output of irrigation after root pruning is higher than that of no irrigation.