臺灣博碩士論文加值系統

使用 28 個家系, 280 株之台灣扁柏一年生的苗木,研究台灣扁柏四個族
群內的遺傳變異和族群間遺傳分化的程度.利用澱粉膠體電泳技術分析
11 種酵素系統合計 20 個基因座(loci)中,其中 7 個基因座為多形性
(polymorphism).當以 99﹪ 和 95﹪ 為多形性標準時,平均的多形性基因
座百分比分別為 18.8﹪ 和15.0﹪.在不同的族群裡,平均異結合性期望值
的範圍從 0.044 到 0.060,每個體之異結合性基因座百分比其範圍為
4.5 到 8.5,每基因座之等位基因平均數為 1.10 到 1.45,而每基因座等
位基因之有效數目是從 1.05 到 1.08,與其他針葉樹種之值比較,台灣扁
柏的異結合性和每基因座之等位基因數目都偏低,反映出可能為島嶼特性
使然.利用 F-statistics 和基因歧異度分析族群內及族群間遺傳變異所
佔的比例,估計族群間的變異佔總變異的 8﹪,其餘 92﹪ 存在於族群內
,結果顯示族群間的基因交流缺乏有效的阻隔.根據 Nei 公式求得族群間
遺傳距離,顯示族群在地理上的距離和遺傳上的距離並無關連性.

Genetic diversity within and genetic differentiation among
several population of Chamaecyparis taiwanensis Masamune &
Suzuki in Taiwan were investigated using 280 one-year old
progeny be- longing to 28 families. Seven out of the 20 loci
examined were polymorphic. The average proportion of
polymorphic loci per popu- lation was 18.8﹪ and 15.0﹪ at the
99﹪ and 95﹪ criterion for polymorphism. Mean expected
heterozygosity range from 0.044 to 0.060 in the different
population. On average,the percent hetero- zygous per
individual range from 4.5 to 8.5, the number of allele per
locus from 1.10 to 1.45, and the effective number of alleles
per locus from 1.05 to 1.08. The much lower expected
heterozygo- sity and lower number of alleles per locus compared
to other coniferous species probably reflects the insular
nature. Parti- tioning the genetic variability into within and
among population components with F-statistics and gene
diversity analysis led to an estimate of within population
variation amounting to 92% of the total variation, only about
8﹪of the total genetic diversity existed among population.
These suggest a lack of barriers to gene flow among population.
Genetic distance between populations was not correlated to the
geographical distance.