小花草玉梅花序水平上雌性适合度成分变化

Intra-inflorescence variation in female fitness components in Anemone rivularis var.flore-minore

生活在高寒地区的植物究竟会采取何种繁殖对策来保障其雌性繁殖成功,已经引起了很多学者的关注。本研究通过野外调查采样对青藏高原东缘多年生草本植物小花草玉梅(Anemone rivularis var.flore-minore)花序水平上不同级别枝条部位雌性适合度成分变异进行了研究。发现随着花从一级枝到三级枝开放的次序,小花草玉梅每花胚珠数和每果种子质量在不同生境中表现不同。每果种子数均以二级枝最高;每果单个种子质量由一级枝向三级枝显著降低(P<0.001);而结籽率和雌性分配均不依赖于花序枝级部位;各雌性适合度成分间均存在正相关关系。

It has been noticed that the plants in the alpine region should adopt different reproductive strategies to ensure the successful female reproduction. The variations of female fitness components of intra-inflorescence were investigated in different branch positions in the perennial hermaphrodite herb Anemone rivularis var. flore-minore from the Qinghai-Tibet Plateau. The results showed that ovule number per flower and mean seed weight per fruit varied with the flowers＇ open order from the first branch to the third branch in different habitats. The seed number per fruit at the second branch was highest, while single seed weight per fruit significantly decreased （P〈0.001） from the first branch to the third branch. The seed-setting rate and female allocation did not depend on inflorescence branch part, whereas there were significantly positive correlations between female fitness components.