為探討台灣野生狼尾草 (Pennisetum purpureum) 之分佈及其遺傳歧異度，本試驗自台灣15 個地區搜集104 個樣本，並以狼尾草台畜草2 號為對照，利用逢機增殖多型性DNA (random amplified polymorphic DNA, RAPD)技術，分析樣本間之遺傳歧異度。結果顯示，以AMOVA (analysis of molecular variance)進行變方分析，顯示族群內變方佔總變方之94.18% (p<0.001) 且達顯著性差異。各縣市之遺傳距離介於0.0003 至0.3 之間，以遺傳距離0.03 為截點則可將104 個樣本分為7 群，分別為第1 群：台北、新竹；第2 群：苗栗；第3 群：桃園；第4 群：台東、屏東；第5 群：台中、南投、花蓮、彰化、雲林；第6 群：台南、嘉義、高雄；第7群：宜蘭。遺傳距離與樹狀圖的相關係數r 為0.68。綜合上述，此7 群狼尾草種原足以進一步進行選拔評估，以期在短時間內篩選出具高品質潛力之狼尾草。

Napiergrass (Pennisetum purpureum) is one of the most important forage crops inTaiwan. The hybrid seeds of napiergrass spread widely. It causes diverse germplasms ofnapiergrass in the field. In this experiment, 104 samples of native napiergrassgermplasms were collected from 15 areas in Taiwan. The genetic diversity of thesenapiergrass germplasms were determined by random amplified polymorphic DNA(RAPD) analysis. The results showed that 94.18% (p<0.001) variance within thepopulation was significantly different by analysis of molecular variance (AMOVA).The hereditary-distance was ranged from 0.0003 to 0.3 among the 15 areas. With theherediary-distance of 0.03, the 104 napiergrass germplasms could be divided into 7groups: the 1st group from Taipei and Hsinchu, the 2nd group from Miaoli, the 3rdgroup from Taoyuan, the 4th group from Taitung and Pingtung, the 5th group fromTaichung, Nantou, Hualien, Changhua and Yunlin, the 6th group from Tainan, Chaiyiand Kaohsiung, and the 7th group from Eilan. The correlation coefficient between thegenetic distance and the cluster dendrogram was 0.68. Taken together, the resultssuggested that napiergrass lines from the 7 groups might be sufficient for furtherevaluation to select the elite lines within a shorter period