喜马拉雅紫茉莉瘦果粘液对种子低温萌发的保护  

Roles of Achene Mucilage in Defensing Freezing Injury for the Seed Germination of Mirabilis himalaica

作　　者：卢骁[1] 兰小中[2] 杨凤娇[1] 马世尧[1] 刘胜利[1] 玉猛[1] 贺茜[1] 陈玉珍[1] 

机构地区：[1]北京林业大学生物科学与技术学院林木育种国家工程实验室,北京100083 [2]西藏农牧学院食品科学学院,西藏林芝860000

出　　处：《草地学报》2014年第6期1281-1287,共7页Acta Agrestia Sinica

基　　金：国家科技支撑计划项目(2011BAI13B06)资助

摘　　要：以采自西藏林芝的喜玛拉雅紫茉莉(Mirabilis himalaica)瘦果为材料,了解瘦果结构组成、淀粉颗粒对瘦果TTC活性检测的影响,及不同吸胀时间瘦果抵抗低温胁迫的效果,以揭示瘦果分泌粘液在萌发过程中的低温保护作用。结果表明:瘦果由果皮、种皮、胚和淀粉颗粒组成,淀粉影响了TTC检测细胞活性的准确性,并发现成熟瘦果有分泌粘液的特性;瘦果发芽的适温为15℃;TTC法检测瘦果细胞活力显示,吸胀72h是研究低温胁迫对喜马拉雅紫茉莉瘦果萌发影响的较适宜时间;吸胀72h的瘦果低温胁迫处理后再进行萌发试验,-5℃和-10℃处理的瘦果在发芽进程中后期有粘液瘦果发芽率比去掉粘液瘦果的发芽率高8.3%左右。Achenes of Mirabilis himalaica,an alpine medical plant distributed in the Linzhi area （Elevation：3000 m） of Tibet,produced a pectinaceous mucilage layer that could imbibe a large amount of water.Observations under stero microscope show that M.himalaica achene is composed of pericarp,seed coat,embryo and starch.The main aim of this study is to explore the role of mucilage in the seed germination of this alpine plant under freezing stress.Germination tests indicate that the optimum temperature of seed germination is 15℃.The activity of achene tissue is tested by triphenyl tetrazolium chloride （TTC） method.Results indicate that the starch of achenes seriously affects the accuracy of the TTC method.And the optimum incubation time of the study is 72 hours.The germination rates of seeds with or without mucilage （demucilaged） declined at-5℃ or-10℃.However,the germination rate of achene with mucilage was significantly higher than that of the demucilaged ones after freezing stress.Both germination tests and TTC method indicate that achene mucilage presumably plays an important role in the life cycle of M.himalaica by aiding germination in the stressful habitats of Tibet alpine environment.

关 键 词：喜玛拉雅紫茉莉 瘦果 粘液 低温 萌发 

分 类 号：Q945.34[生物学—植物学]