【摘要】 为了研究多枝柽柳的两季开花物候特征与生殖特性,对分布于古尔班通古特沙漠南缘莫索湾荒漠区的多枝柽柳自然种群各水平的开花物候指数、开花过程中的花部特征变化和结实特性进行了观察和统计。结果表明:(1)多枝柽柳春花期为5月下旬至6月上旬,表现为"集中开花模式",夏花期为6月中旬至9月上旬,表现为"持续开花模式"。(2)多枝柽柳春、夏花期的群体、个体、花序和单花水平的花期持续时间分别为14d、10d、3d、1d和85d、77d、2d、1d。(3)花序水平上夏花期始花日期、开花持续时间、开花数和座果数两两之间均存在显著相关关系。(4)两季花期间单花水平的开花进程与形态结构没有明显差异。(5)春花期的结实率显著高于夏花期,但两季花期结籽率差异不显著。(6)春花期昆虫访花次数显著高于夏花期。(7)两季花期的花粉活力没有明显差异,春花期的柱头可授性持续时间比夏花期长。研究认为,古尔班通古特沙漠南缘莫索湾荒漠区的生境条件恶劣,多枝柽柳特殊的春、夏两季开花结实特性在一定程度上提高了其生殖成功的可能性,是对特殊生境的适应性表现。更多还原

【Abstract】 Our aim is to investigate bi-seasonal flowering phenology and reproductive features of Tamarix ramosissima.The study was conducted in wilderness region of Mosuowan which is located at the southern edge of Gurbantunggut Desert.We observed the flowering phenology index,flower characteristics changes of the flowering course and fruit set characteristics in the wild population of T.ramosissima.The results showed that:(1)the spring flowering period of T.ramosissima.was from the late May to early June,exhibiting a"mass-flowering"pattern.The summer flowering period was from the middle June to early September,exhibiting an"extended-flowering"pattern.(2)In the spring flowering period and the summer flowering period,the flowering duration of the population,individuals,inflorescences and single flower were 14,10,3,and 1 d,and 85,77,2,and 1 d,respectively.(3)There were significant correlation among first flowering date,flowering duration,flower number and fruit number at inflorescences of the summer flowering period.(4)There was no significant differences in the flowering process and morphological structure between two flowering periods.(5)The fruit rate and seed rate in spring flowering period are same higher than that in the summer flowering period,but there was no significant difference between two flowering periods.(6)Pollination times in spring flowering period is significantly higher than that in summer flowering period.(7)There was no significant differences in the pollen vitality between two flowering periods,the stigma receptivity in spring flowering period is longer than that in summer flowering period.The survival conditions in wilderness region of Mosuowan is poor,bi-seasonal flowering phenology and reproductive features of T.ramosissimaraise the possibility of their reproductive success.更多还原