The spatial genetic structure (SGS) of a plant population is mainly determined by gene flow via seed and pollen, various natural selection pressures and spatial patterns of existing plants. However, the role of those factors in shaping SGS requires further study.
With support of the National Science Foundation of China, Dr. Zhou Huiping and her supervisor Prof. Chen Jin of Xishuangbanna Tropical Botanical Garden (XTBG) studied the relative importance of those factors in shaping the SGS of an understorey dioecious ﬁg species(Ficus cyrtophylla).
Fig plants are best known for their species-specific interactions with pollinating wasps and they are also recognized as the key food resources for tropical frugivores. For such a special group, understanding the contributions of seed dispersers and wasp pollinators to gene flow and genetic stucture is always a central question.
The study was conducted in a limestone mountain area (21°54'07"-21°55'20"N，101°16'05"-101°17'04"E)of south-east Xishuangbanna, Yunnan province, China.
The researchers used a focal population of the dioecious ﬁgs pecies Ficus cyrtophylla (a bird-dispersed shrub or small tree species) to evaluate the following factors which drive gene flow and spatial genetic structure (SGS): (i) the patterns of seed rain and existing plant distribution; (ii) the effects of dispersers and microhabitat on seed rain; (iii) the effective gene dispersal distance via seed and pollen and their relative contributions to the gene flow; (iv) the roles of gene flow and local selection in determinin SGS across different life stages.
Results from this study showed that seeds,seedlings and trees of F. cyrtophylla all exhibit clumped distribution patterns.
Entitled with “Spatial genetic structure in an understorey dioecious fig species: the roles of seed rain, seed and pollen-mediated gene flow, and local selection”, the research detail has been published online in Journal of Ecology, doi:10.1111/j.1365-2745.2010.01683.x