Genetic diversity and gene conservation of Pacific silver fir (Abies amabilis) on Vancouver Island, British Columbia [Canada]
1997
Davidson, R. (British Columbia Univ., Vancouver (Canada). Dept. of Forest Sciences) | El-Kassaby, Y.A.
Levels of inbreeding and patterns of genic diversity of eight Vancouver Island Pacific silver fir (Abies amabilis (Dougl.) Forbes) populations were determined using genetic variation at 13 allozyme loci. With the exception of one locus, the segregation analyses for all polymorphic loci exhibited distinct, co-dominant expression and simple Mendelian segregation in their mode of inheritance. Estimates of inbreeding varied among populations and ranged from zero to as much as 27%. A highly positive correlation of population mean seed size and multilocus outcrossing rate was observed (r=0.712, 0.05 P 0.10). Similar to most studied conifers, low level of population differentiation was observed. Nei's genetic diversity analysis produced a GST value of 0.051 indicating that the vast majority of allelic variation (95%) resides within an individual population. The average genetic distance among all populations was low (0.0112) and the correlation between genetic and geographic distances was not significant, with geographical distance, explaining only 1.4% of the variation in genetic distance among pairs of populations. A novel approach for determining the relative importance of genetically unique populations for genetic conservation purposes was presented. Finally, a proposal for combining utilization (the establishment of seed production areas) and conservation (gene conservation of unique populations) was presented
显示更多 [+] 显示较少 [-]