异子蓬二态性种子萌发对生境条件的响应  

Response of Germination of Dimorphic Seeds of Borszczowiz aralocaspica to Habitat Conditions

作　　者：李利[1] 杨小林[1] 王伟华[1] 

机构地区：[1]中国科学院新疆生态与地理研究所

出　　处：《干旱区研究》2007年第6期830-834,共5页Arid Zone Research

基　　金：中国科学院"西部之光"人才培养计划项目(2005);中国科学院新疆生态与地理研究所"绿洲学者"项目(0671051)

摘　　要：试验研究了异子蓬（Borszczowiz aralocaspica）的果实多态性表现,并通过培养箱萌发试验,对其大小2种类型种子的萌发特性进行了研究。结果显示：大种子能在10-35℃的范围内萌发,萌发适应温度范围宽,萌发速度快,同时能够在1.3 mol/L的NaC l溶液中萌发,对盐分的忍耐能力极强;小种子一般适于在30℃以上较高的温度下萌发,萌发受到盐分的强烈抑制,萌发缓慢,表现出一定的休眠现象,但当盐浓度降低时,具有一定的萌发恢复。这意味着异子蓬的大种子和小种子具有不同的萌发策略。因此得出,异子蓬通过形成2种类型的种子,而将2种不同的萌发策略统一于一体,增加了对环境的适合度,有利于在不利条件下的定居和生长。Borszczowiz aralocaspica （Chenopodiaceae）, an early annual species growing in saline habitats in the Junggar Basin, northwest China, produces seeds with two sizes, i.e. the large and small seeds. In this study, the germination differences between the two kinds ofB. aralocaspica seeds are lucubrated so as to investigate their ecological roles. The large seeds are heavier and light brown, and they have a utricle swollen, whereas the small seeds were lighter and black. The study results reveal that there are some obvious germination differences between the seed kinds： the large seeds can rapidly germinate at a wider temperature range of 10 ℃-35 ℃, and their salt tol- erant capability is higher than that of small seeds because their germination percentage is over 46% - 11.5% in NaCl solution with concentration of 1.3 mol/L. The optimal germination temperature of the small seeds is over 30℃, their germination is slow and is strongly affected by salt content of NaCl solution, that is their germination rate is increased when the salt content of NaCl solution is decreased. Therefore, it can be concluded that the germination of the two kinds ofB. aralocaspica seeds is different, so the different germination conditions should be considred in the germination experiment.

关 键 词：异子蓬(Borszczowiz aralocaspica) 种子 多态性 萌发 盐分 

分 类 号：Q945.7[生物学—植物学]