雨养条件下植物生长调节剂对冬小麦根系生长和产量形成的调控研究

为了探讨雨养模式下植物生长调节剂协同调控冬小麦根系生长和产量形成的机理,在华北平原雨养条件下,研究烯效唑和矮壮素复配剂以及清水对照对冬小麦产量形成、群体数量和根系生长的影响。结果表明:植物生长调节剂处理显著提高冬小麦穗数和籽粒产量,但是对小穗数和穗粒数没有显著影响。植物生长调节剂可以促进冬小麦冬前分蘖,明显提高生育前期群体数量。植物生长调节剂处理下,冬小麦分蘖期单株根系根长和根表面积显著降低,但是冬小麦单株根直径、根条数、根重和根冠比显著增加。植物生长调节剂处理主要影响冬小麦分蘖期0~30 cm土层的根长密度和0~50 cm土层的根重密度,而对深层土壤中的根长密度和根重密度影响较小。植物生长调节剂可以协同调控冬小麦根系生长和分蘖形成,从而有利于塑造合理群体结构和提高产量。

Effect of Plant Growth Regulator on the Root Growth and Yield Formation of Winter Wheat under Rain-fed Condition

In order to study the coordinated regulation mechanism of plant growth regulator on winter wheat root growth and yield formation under rain-fed condition,a field experiment was conducted to determine effects of differ-ent treatments (the mixture of uniconazole and chlormequat chloride and water control)on yield formation,popula-tion quantity and root growth of winter wheat under rain-fed condition in the North China Plain.These results sug-gested that plant growth regulator significantly increased spike number and grain yield,but had no marked effect on spikelet number per spike and kernel numbers per spike.Plant growth regulator could promote the tillering of winter wheat before winter and enhance population quantity in early growth stage.Under plant growth regulator treatment, winter wheat root length and root surface area per plant were decreased significantly,however,root diameter,root number,root weight and root /shoot ratio per plant were significantly increased.At tillering stage,plant growth regu-lator had effect on winter wheat root length density in 0 -30 cm soil layer and root weight density in 0 -50 cm soil layer but had no effect in the deep soil layer.Plant growth regulator could coordinated regulated root growth and till-er formation of winter wheat,which contributed to shape reasonable population structure and increase yield.