解除休眠的水曲柳种子对不同脱水条件的萌发和生理响应  

Germination and Physiological Responses of Dormancy Released Seeds of Fraxinus mandshurica to Dehydration in Different Conditions

作　　者：张鹏[1] 宋博洋[1] 吴灵东[1] 沈海龙[1] 

机构地区：[1]东北林业大学林学院,哈尔滨150040

出　　处：《林业科学》2017年第3期60-67,共8页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目(31000301)

摘　　要：【目的】比较不同脱水条件对解除休眠的水曲柳种子干燥脱水后萌发的影响,并探索在不同条件下脱水过程中种子内部的生理变化,为解除休眠水曲柳种子的再干燥贮藏提供理论和技术依据。【方法】以解除休眠的水曲柳种子为材料,采用单因素设计,比较种子在7种温度(5,10,15,20,25,30,35℃)条件下干燥脱水后的萌发能力,再设计双因素试验,分析脱水温度(常温20℃和低温5℃)、脱水速率(快速和慢速)及其交互作用对干燥脱水后种子萌发的影响,并测定不同脱水条件下种子中抗氧化酶(SOD、POD和CAT)活性,丙二醛(MDA)含量,可溶性糖、可溶性蛋白和淀粉含量,以确定种子细胞膜透性、抗氧化系统酶活性和贮藏物质代谢对不同脱水处理的响应。【结果】经不同温度脱水处理后种子的发芽率和发芽指数呈现随脱水温度的升高先上升后下降的趋势,种子发芽时间则呈现出随脱水温度上升而先下降后上升的趋势。常温(20℃)脱水种子的发芽能力最强,高温(35℃)或者低温(5℃)脱水种子发芽能力较弱。与常温脱水相比,低温脱水种子相对电导率和丙二醛含量显著增加,胚中POD和CAT酶活性显著降低,种子中可溶性糖和淀粉含量无明显变化,但可溶性蛋白含量显著降低。与慢速脱水相比,快速脱水种子相对电导率和丙二醛含量显著增加,胚中SOD和POD酶活性显著降低,种子中可溶性糖和淀粉含量无明显变化,但可溶性蛋白含量显著降低。【结论】解除休眠的水曲柳种子最适的干燥脱水温度是20℃,高温(35℃)或者低温(5℃)脱水会导致种子发芽率和发芽指数下降,发芽时间延长。低温(5℃)或快速脱水后种子细胞膜透性和丙二醛含量显著增加,种子中可溶性蛋白含量和胚中抗氧化酶活性均显著降低,从而引起种子萌发能力下降。胚中的抗氧化酶活性对低温和快速脱水反应不同,POD和CAT对低温脱水�[ Objective ] We compared the effects of different dehydration conditions on germination of dormancy-released seeds of Fraxinus mandshurica and explored the intrinsic physiological changes of seeds under different conditions to provide theoretical and technical basis for redrying and storage of dormancy-released seeds of F. mandshurica. [ Method ] Using single factor design, the dormancy released seeds of F. mandshurica were used to investigate seed germination ability after dehydration at different temperatures（5, 10, 15, 20, 25, 30, 35 ℃ ）. Then, the effects of dehydration temperature （normal temperature 20 ℃ and low temperature 5 ℃ ）, dehydration speed （slow and fast）, and their interaction on seed germination after dehydration were investigated using two factor design. In order to determine the response of seed cell membrane permeability, antioxidant system enzyme activity and storage material metabolism to different dehydration treatments, the activities of antioxidant enzymes （SOD, POD and CAT） , malondialdehyde （MDA） content, soluble sugar, soluble protein and starch contents in seeds under different conditions were measured. [ Result ] The seed germination rate and germination index showed the trend of increasing at the beginning and then decreasing with the rising of the dehydration temperature, and the germination time of seeds showed the opposite trend. The germination ability of seeds dehydrated at normal temperature （20 ℃ ） was the best, and the germination ability of seeds dehydrated at high temperature（35 ℃ ） or low temperature（5 ℃ ） was weak. Compared with the normal temperature dehydration, the relative electrical conductivity and MDA content of seeds dehydrated at low temperature increased significantly, the POD and CAT enzyme activity in embryos was significantly decreased, no significant changes in the contents of soluble sugar and starch in the seeds, but soluble protein content decreased significantly. Compared with the slow speed dehydration, the

关 键 词：水曲柳 脱水耐性 种子萌发能力 细胞膜透性 抗氧化酶活性 可溶性蛋白 

分 类 号：S718.43[农业科学—林学]