Micro-geographic landscape features demarcate seedling genetic structure in the stream lily, Helmholtzia glaberrima

作者：Prentis Peter J^*; Mather Peter B

来源：Aquatic Botany, 2007, 87(2): 111-115.

DOI：10.1016/j.aquabot.2007.03.007

• dispersal
• genetic diversity
• Helmholtzia
• hydrochory
• landscape
• Philydraceae
• riparian
• southern Queensland

In this study, 169 stream lily (Helmholtzia glaberrima) seedlings from six micro-drainages were genotyped with AFLP markers to quantify the impact that topographic landscape features and altitude may hake in shaping patterns of genetic diversity within individual populations. A global analysis of genetic diversity detected significant genetic differentiation among micro-drainages (F-ST = 0.22, P < 0.01). The observed genetic structure of sampled sites conformed to a hierarchical model of gene flow. Assignment tests also supported a hierarchical model of gene flow as only one dispersal event among the sampled micro-drainages was detected. This suggests that opportunities for seed dispersal in H. glaberrima are highly constrained by patterns of hydrographic networks even at a local scale. In contrast, altitude had little impact on partitioning of genetic diversity as no increase in genetic diversity was evident among individuals in the upper (0. 18 +/- 0.02), and lower (0. 17 0.02) areas of micro-drainages. Overall these results suggest that the influence of freshwater landscape features can vary widely the effect on the patterns of genetic diversity of seedlings in stream lily populations.

• 出版日期2007-8