RESUMEN
We examine the diversity of six microsatellite loci and partial RAG1 exon of "barabensis" and "pseudogriseus" karyoforms in Cricetulus barabensis sensu lato species complex. A total of 435 specimens from 68 localities ranging from Altai to the Far East are investigated. The results of the population structure analysis (factor analysis and NJ tree based on Nei genetic distances) support subdivision into two well-differentiated clusters corresponding to the two karyoforms. These karyoforms are also well differentiated by the level of microsatellite variability. In several "barabensis" specimens, we found microsatellite alleles that are common in "pseudogriseus" populations but are otherwise absent in "barabensis." Most of these specimens originate from a single population in one of the zones of potential contact between karyoforms, Kharkhorin in Central Mongolia. These molecular results are consistent with previously published karyological data in suggesting that rare hybridization events between the two chromosomal races occur in nature.
Asunto(s)
Cricetulus/genética , Flujo Génico , Sitios Genéticos , Variación Genética , Repeticiones de Microsatélite , Animales , SiberiaRESUMEN
Aspen Populus tremula L. (Salicaceae) is the fast-growing tree species of environmental and economic value. Aspen is capable of reproduction by both seeds and vegetative means, forming root sprouts. In an adult stand, identification of ramets of one clone among the trees of seed origin based on their morphology is difficult. A panel of 14 microsatellite loci developed for individual identification of aspen was applied for the clonal structure analysis in four natural aspen stands of the European part of Russia: Moscow and Voronezh oblasts, the Mari-El Republic, and the Republic of Tatarstan. In 52 trees from the Moscow sample, 41 multilocus genotypes were identified; in the Voronezh sample, among 30 individuals, 25 different genotypes were detected; and in the sample from Mari-El, 32 trees were represented by 13 genotypes. In the stand from Sabinsky Forestry, Tatarstan, all of the examined 29 trees were represented by a single genotype. The ancestral tree carrier of this genotype which was the most heterozygous (0.929) among all studied aspen individuals (sample mean, 0.598) obviously has spread over a large territory during several cutting and reproduction cycles, currently occupying the area of 2.2 ha. For aspen, usually suffering from Aspen trunk rot, such high viability is evidence of resistance to the main pathogens. The revealed superclone deserves further study with karyological methods and flow cytometry to determine ploidy level and analysis of the growth rate and the quality of wood for possible use in plantation forest production.