Microsatellite variation of Quercus aquifolioides populations at varying altitudes in the Wolong Natural Reserve of China

Abstract

Genetic variation and differentiation were investigated among five natural populations of Quercus aquifolioides occurring along an altitudinal gradient that varied from 2000 to 3600 m above sea level in the Wolong Natural Reserve of China, by analyzing variation at six microsatellite loci. The results showed that the populations were characterized by relatively high intra-population variation with the average number of alleles equaling 11.33 per locus and the average expected heterozygosity (H E ) being 0.779. The amount of genetic variation varied only little among populations, which suggests that the influence of altitude factors on microsatellite variation is limited. However, there is a significantly positive correlation between altitude and the number of low-frequency alleles (R 2 = 0.97, P < 0.01), which indicates that Q. aquifolioides from high altitudes has more unique variation, possibly enabling adaptation to severe conditions. F statistics showed the presence of a slight deficiency of heterozygosity (F IS = 0.136) and a low level of differentiation among populations (F ST = 0.066). The result of the cluster analysis demonstrated that the grouping of populations does not correspond to the altitude of the populations. Based on the available data, it is likely that the selective forces related to altitude are not strong enough to significantly differentiate the populations of Q. aquifolioides in terms of microsatellite variation.

Natural regeneration of Fagus sylvatica L. adapts with maturation to warmer and drier microclimatic conditions

“…This would be the case in our study for the potential outlier loci, which without being adaptive markers, could be used for the identification of selection effects. Similar selection effects have been reported in genetic studies of different oak species by using nuclear microsatellites (Neophytou et al, 2010;Ramirez-Valiente et al, 2010;Zhang et al, 2006). Further, large changes in allele frequencies at eight microsatellite loci observed in Drosophila populations indicated selectively-driven changes and provided evidence about genomewide selective sweeps that affect not only fitness but also linked neutral loci (Montgomery et al, 2010).…”

Genetic diversity and population structure of Castanopsis eyrei based on simple sequence repeat markers

“…We found that the medium-altitude population had the highest genetic diversity; a similar result was obtained for Quercus aquifolioides in Wolong Nature Reserve (Zhang, 2006). The high genetic diversity observed in the medium-altitude population may be attributable to the better habitat there.…”

“…The genetic differentiation of populations at different altitudes has been detected in some species (Bellusci et al, 2005;Zhang, 2006); however, some studies have reported little or no genetic variation between populations at different altitudes (Aradhya et al, 1993;Oyama et al, 1993;Gehring and Delph, 1999). In this study, SSR markers, combined with population genetic theory, were used to study the genetic diversity and population genetic structure of C. eyrei with changing altitude.…”

Genetic structure of mossesPleurozium schreberi(Willd. ex Brid.) Mitt. andRacomitrium lanuginosum(Hedw.) Brid. along altitude gradients in Hokkaido, Japan

“…Chen et al, 2008), while only little or no differences with respect to altitude have also been reported (e.g. Zhang et al, 2006;see also, Ohsawa & Ide, 2008). Effective dispersal is a key factor that prevents the development of altitudinal structuring in genetic variation patterns.…”