【摘要】 对分布在青藏高原东缘高寒草甸常见种长毛风毛菊的6个海拔梯度(3200～3850m)18个居群的繁殖分配进行了研究,结果表明:长毛风毛菊随海拔的升高个体和营养器官减小,繁殖的投入增加;随着海拔的升高,长毛风毛菊的个体管状小花数目和种子数目减少,管状小花重量和百粒重增大;个体管状小花的数目及重量和个体种子的数目及重量间存在权衡关系;长毛风毛菊的个体大小和繁殖分配存在负相关关系。在资源受限的环境下,长毛风毛菊以减少管状小花数目和种子的数目来增加管状小花重量和百粒重,是保证有性繁殖成功的策略之一。更多还原

【Abstract】 Saussurea hieracioides (Asteraceae) is a wide spread species in the eastern margin of Qinghai-Tibetan Plateau. This paper studied the reproductive allocation (RA) strategy of the 18 S. hieracioides populations in 6 altitudinal belts along the elevation from 3200 to 3850 m. The results showed that with increasing altitude, the plant individual size and vegetative input decreased, but the reproductive input increased. The number of disk florets and matured seeds per individual declined, while the weight of disk florets and 100-grain increased with increasing altitude, and there was a trade-off between the number and weight of both disk florets and matured seeds at individual level. The RA was negatively correlated with the plant individual size among all the populations. It was suggested that in the resources-limited environment, S. hieracioides could increase its tubular floret weight and 100-grain weight at the expense of reducing the number of both tubular floret and seed as one of the strategies to guarantee the success of sexual reproduction.更多还原