几种沙棘种子萌发及幼苗生长期淀粉酶活性的变化

Variation of Amylase Activity in the Seed Germination and Seedling Growth Periods of Some Hippophae Species

[目的]探索沙棘种子萌发的生理机制。[方法]采用3,5-二硝基水杨酸法研究沙棘种子萌发及幼苗生长期淀粉酶活性的变化及温度、pH值、底物浓度对其影响。[结果]不同沙棘种子在萌发过程中的淀粉酶活性不同。在3种沙棘中,阿尔泰新闻的酶活性最高,且一直上升,向阳的酶活性最低,优胜的酶活性随种子的萌发先增加后降低。淀粉酶的活性在pH值为6.8时最高。酶活性随着底物(1%淀粉)浓度的增大而增加,但当底物浓度增加到一定值(6%)时,酶活性趋于平稳。沙棘种子萌发期淀粉酶的最适温度为45℃,高于或低于最适温度都会影响酶的活性,且温度过高会使酶失活。[结论]该研究为开发利用沙棘资源提供了理论依据。

[Objective] The purpose was to explore the physiological mechanism of seed germination of Hippophae rhamnoides.[Method] The variation of amylase activity in the seed germination and seedling growth periods of H.rhamnoides and the influences of temperature,pH value and substrate concn.on the activity variation were researched by 3,5-dinitrosalicylic acid method.[Result] The amylase activities in the germination processes of different H.rhamnoides seeds were different.Among the 3 hippophae species,the amylase activity was highest and always increasing in AETXW and lowest in Xianyang. The amylase activity in Yousheng was first increased and then decreased as the seeds were germinating. When pH value was 6.8, the amylase activity was highest. As the substrate （ 1% starch） concn, was increased, the amylase activity was increased. But when the substrate concn, was in- creased to a certain value （6%）, the amylase activity changed to be steady. The fittest temperature for amylase in the seed germination period of H. rbamnoides was 45℃, both higher and lower temperatures would intluence amylase activity and too high temperature would deactivate amylase.