油菜素内酯促进小麦灌浆结实及其生理基础的研究

THE PROMOTION 0N THE MILKING AND FORMATION OF GRAINS IN WHEAT AND ITS BIOLOGICAL MECHANISM

在小麦开花结实期,用0.01ppmBR给植株喷雾,可促进籽粒灌浆,提高千粒重和每穗结实粒数。分析BR促进小麦增产的生理基础表明,BR处理对旗叶叶绿素和可溶性蛋白质含量无明显影响,但可增加新的蛋白质组分,改变不同组分之间的比例关系。BR提高叶片的光合速率,增加碳素同化产物的总供给;促进叶片同化产物向外输出,增加光合产物在穗部尤其是弱势小穗中的分配比例。还可提高前期发育中幼穗体内IAA含量以及灌浆末期的小穗内和籽粒内ABA含量,改变穗部IAA和ABA的平衡关系,从而有利于促进受精子房的生长和淀粉的累积。

The milking speed of grains, number of grains per ear and 1000-grain weight werepromoted following 10^(-2)ppm Brassinolide (BR) solution spraying treatments duringwheat flowering period. The data indicated that BR had no significent effect on thecontent of chlorophyll and soluble proteins, but it induced new components of proteinsand altered their relative proportions BR treatment also increased CO_2 assimilationrate and supply of photosynthate, promoted the transportation of assmilate to car, espe-cially to the low-potence spikelets. The results also showed that BR increased IAAlevels in earyl developing spikelets and ABA levels in spikelets and grains duringmealy-hard stage, indicating an alteration in the balance of endogenous IAA and ABAin ear, and as a result, growth of fertilized ovary and accumulation of starch ingrains were enhanced.