Variance effective population size based on multilocus gamete frequencies in coniferous populations: an example of a Scots pine clonal seed orchard

Abstract

The temporal method for estimating variance effective population size (Ne) based on allozyme multilocus gamete frequency data in coniferous populations is proposed. The method was applied to a Scots pine (Pinus sylvestris L.) seed orchard consisting of 32 clones (parents), and the genotypes of pollen gametes fertilizing 1280 (N) viable seed embryos (progeny) were identified. The gametic frequency estimate of variance effective population size indicated that the progeny population (its part attributed to pollen contribution) was equivalent to 105.3 individuals in an idealized theoretical population, whereas the estimate based on allele frequencies (traditional method) was 156.7 individuals. However, the estimates did not differ statistically. The ratio N̂e/N was very low (0.0823 and 0.1224 for the gametic and allele frequency methods, respectively), indicating nonrandom contributions of male parents to the progeny generation. The advantages of using the gametic frequency estimates of variance effective population size instead of estimates based on allele frequencies are briefly discussed.