Population structure and parentage analysis of black poplar along the Morava River

Abstract

Twelve nuclear microsatellite markers were used to assess the population genetic structure of the riparian pioneer tree species Populus nigra L. along the Morava River in the Czech Republic. Parentage analysis of 30 seedlings was performed to examine the extent of hybridization between P. nigra and introduced hybrid poplars and to determine the distances of pollen and seed movement. Additionally, spatial genetic structure was analysed and gene dispersal was estimated indirectly. In spite of the limited size of our studied population (65 adult trees), the apparent overall genetic diversity was high (expected heterozygosity He = 0.82) and comparable to the known diversity of P. nigra in southern Europe, where its glacial refugia were located. Introgression of Populus deltoides Bartr. ex Marsh. genes to P. nigra was confirmed, since 13% of tested seedlings descended from a Populus ×canadensis Moench female. The results of parentage analysis showed that a low percentage (20%) of offspring originated from parents located outside the study site. Dispersal distances for pollen and seeds movement ranged from 10 to 230 m and from 163 to 370 m, respectively. The study revealed significant spatial genetic structure (regression slope –0.0158), which was probably caused by limited gene flow.

Genetic structure of the old black poplar population along the bank of the Vistula River in Poland

“…1), which is in agreement with previous genetic studies of Populus nigra employing a variety of genetic marker systems [13][14][15][16][17][18]. All nSSR loci were highly polymorphic.…”

Gene flow in poplar - experiments, analysis and modeling to prevent transgene outcrossing

“…Because of the high exclusion power needed for parentage analysis (Marshall et al 1998), studies on seed dispersal in literature are few. There is only one other study on explicit seed dispersal estimation for P. nigra (Pospísková & Sálková 2006). Within a small population along the Morava river, they found seed dispersal distances ranging from 163 to 370 m. The difference in respect to our results may be due to the small scale of their investigation.…”

“…Tabbener & Cottrell (2003) for P. nigra found pollination distances between 25-350 m and DiFazio et al (2004) reported mean pollination distances for Populus trichocarpa between 140-1100 m, with a strong dependency on the area sampled. This finding have been confirmed by Pospísková & Sálková (2006), who found effective pollination distances of 10-230 m within a population of 65 adult trees and 30 analyzed seedlings of P. nigra along the Morava river.…”

Sex-specific pattern of spatial genetic structure in dioecious and clonal tree species, Populus alba L.

“…For over 30 % of individuals from the studied population, full-sibling relationships were inferred, which strongly suggests the predomination of within-population crossings and recruitment events. Based on parentage analysis, Pospíšková and Šálková (2006) indicated domination of within-population pollinations in studied black poplar stands-77 % of offspring were fathered by males from the local population.…”