Genetic Structure and the Mating System in an Old Stand of Polish Larch

1991

S. 75-78

3 Tab., 25 Lit. Ang.

Unselbständiges Werk

200051259

The genetic structure and the mating system were investigated in a 250 year old stand of Polish larch (Larix decidua subsp. polonica (Ragib.) Domin) using six allozyme marker loci (Gdh, Mdh-1, Mdh-2, Mdh-3, Shdh, Srdh). The average expected heterozygosities, based on these loci were 0.189 and 0.187 for the parental and filial generation respectively, and the mean expected heterozygosity for the mature stand based on 18 gene loci was calculated to be 0.193. An excess of heterozygotes was found in the mature forest population. Single-locus estimates of outcrossing rate ranged from 0.776 to 1.132 (minimum variance mean 1.048), while the multilocus estimate was 0.943. Detected amount of selfing and heterogeneity of single-locus estimates were statistically significant. The calculated ratio of genetically effective male individuals to receptive female individuals was only 0.22 in this population.