利用ISSR分子標誌檢測臺灣紫色狼尾草（Pennisetum purpureum Schum）遺傳歧異度

Abstract

Purple napiergrass (Pennisetum purpureum Schum) is a native grass species in Taiwan. In this study 71 samples collected from 15 counties in Taiwan were used and ISSR marker from UBC (University of British Columbia) was used to determine the genetic structure. PCR amplification with 15 ISSR primers yielded 205 DNA fragments, and 101 of these DNA fragments were polymorphic (49.26 %). POPGENE analysis revealed total gene diversity (H), genetic differentiation index (Gst) and gene flow (Nm) were 0.2215, 0.4205 and 0.6892, respectively. Analysis of molecular variance (AMOVA) revealed the variance component among and within populations were 7.55 % and 92.45 %, respectively. This result showed that no significant variation in diversity was observed among populations. The major genetic differentiation was due to variation within populations. In addition, there was no significant relation between genetic distance and geographic distance (r = 0.1137, p＜0.5452) . Both the UPGMA cluster analysis and principal coordinate analysis (PCoA) showed that 71 samples tested could be divided into five groups by 0.04 genetic distance; the first group includes Taipei, Taoyuan, Hsinchu, Miaoli, Taichung, Nantou, Chiayi and Tainan, the second group includes Yilan, the third group includes Changhua and Yunlin, the fourth group includes Kaohsiung, Pintung and Taitung, and the last one includes Hualian. In the future, we can select the elite lines within these five groups by cluster analysis method. It might be helpful to shorten breeding period.