[[alternative]]Study on the Population Genetic Structure of Miscanthus sinensis var. glaber (Nakai) J. Lee

[[abstract]]ABSTRACT The perennial herbaceous Miscanthus sinensis var. glaber (Nakai) J. Lee is a pioneer and early successional status species that can be found in altitude less than 1200 m. A total number of 382 samples of M. sinensis var. glaber from ten localities ranging from Northern, Central and Southern Taiwan were collected to determine their population genetic structure. In addition, 70 samples representing two subpopulations in Northeastern Taiwan were collected for studying the nature selection of microhabitats. Fifteen loci from nine isozymes by Biosys-II were obtained and the results showed that the mean expected value of the heterozygosity ( HE ) is 0.1459 and the proportion of the total diversity among populations ( GST ) is 0.147, that correlated with those of species which disperse seeds by wind. The gene flow rate ( Nm = 1.33 ) and the acquisition of private gene suggest that the gene flow of Miscanthus sinensis var. glaber is retarded. The middle genetic differentiation ( FST = 0.077 ) among the subpopulations in different microhabitate showed the major force that acts on the population genetic structure of M. sinensis var. glaber is local sellection. The mean population genetic similarity ( 0.91 ) between samples from the geographically isolated area, Pei-Ta-Wu Mountain, and those from othe populations collected from rest nine sites is lower than that proposed by Gottlieb ( 0.95 ) and Thrope ( 0.96 ). The results indicated that the population in Pei-Ta-Wu Mountain might have been confined by local selection.