蔗糖和谷氨酰胺及植物激素对水稻离体培养穗淀粉积累的影响

Effects of Sucrose, Glutamine and Plant Hormones in the Culture Medium on Starch Accumulation of Detached Rice Panicles

采用离体穗培养技术研究了蔗糖、谷氨酰胺和不同植物激素对杂交稻组合汕优 10号、KA 2 46 9穗培 4～ 6d籽粒的溶液、蔗糖吸收 ,以及籽粒淀粉积累和淀粉合成的酶活性的影响。在 5～ 15g L蔗糖浓度范围内 ,随着培养液中蔗糖浓度的提高 ,籽粒吸收溶液、蔗糖的量及淀粉积累、蔗糖合成酶、ADPG焦磷酸化酶、淀粉合成酶、淀粉分枝酶活性增加。降低培养液中谷氨酰胺浓度 ,籽粒的物质积累和籽粒活性下降。ABA对淀粉合成的酶有促进作用 ,其余 3种植物激素对离体穗培籽粒吸收溶液和蔗糖及淀粉合成的酶活性有负效应。本研究认为 。

The influences of sucrose, glutamine and plant hormones in the culture medium on the volume of solution and sucrose absorption, starch accumulation in the grain and the starch-synthesis enzyme activities in the endosperm were investigated, with detached panicles of rice hybrid shanyou 10 and KA/2469 cultured 4～6d. Increasing the sucrose supply in the culture liquid from 5g/L to 15g/L resulted in significant increase in the volume of solution and sucrose absorption , starch accumulation in the developing grain. The activities of sucrose synthase, ADP-glucose pyrophosphorylase, starch synthase and branching enzyme were also increased significantly in the developing endosperm. Decreasing the concentration of glutamine in the culture medium reduced starch accumulation and activities of starch-synthesis enzymes. Abscisic acid treatment increased the activities of enzymes that involved in starch synthesis in the developing rice endosperm, but the other hormone treatments showed a negative effects on the volume of solution and sucrose absorption by the grain, and on the activities of starch synthesis enzymes. It is suggested that the starch accumulation in developing endosperm were influenced mainly by the sucrose supply.