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Pakkad Greuk James Celia Torre Franck Elliott Stephen Blakesley David 《New Forests》2004,27(2):189-200
Prunus cerasoides D. Don has been identified as an excellent framework tree species for restoring evergreen forest in seasonally dry tropical forestlands. Here we describe the level of microsatellite variation in P. cerasoides trees within and among three National Parks in northern Thailand: Doi Suthep-Pui, Doi Inthanon and Doi Ang Khang, using published primers developed for peach, sweet cherry and sour cherry. The five microsatellite loci employed detected a total of 41 alleles, with the average number of alleles per locus per study site ranging from 2.7 to 8.0 (n = 82). The value of F
ST over the three sites was 0.115, indicating that while the majority of genetic diversity may be contained within sites, they should be considered as genetically distinct. The implications of this for seed collection of this species for forest restoration are discussed. 相似文献
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Prunus cerasoides D. Don has been identified as a framework species for restoring evergreen forest in seasonally dry climates. The aim of this study was to develop criteria to select parent trees for supplying seed to forest restoration projects based on seedling performance in the nursery and in the field. Seed progenies were collected from 50 individual parent trees; 13 in Doi Inthanon National Park; 14 in Doi Ang Khang; and 23 in Doi Suthep-Pui National Park. Criteria were developed for the selection of superior parent seed trees based on nursery and field performance, and a provisional selection of parent seed trees for forest restoration projects has been made based on these criteria. Four standards for selection of superior seed trees were recognised: (i) 70% or greater seedling survival in the field, (ii) a seedling height of 100 cm or taller after the first growing season in the field, (iii) 40% or greater germination in the nursery and (iv) 70% or higher seedling survival in the nursery. Twenty one seed trees met these standards. 相似文献
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Greuk Pakkad Suad Al Mazrooei David Blakesley Celia James Stephen Elliott Tapio Luoma-Aho Jarkko Koskela 《New Forests》2008,35(1):33-43
This study describes the level of genetic variation and gene flow within and among populations of Prunus cerasoides in rehabilitated sites and adjacent intact forest. The seven microsatellite loci employed detected a total of 75 alleles
(n = 401). Polymorphic information content (PIC) varied from 0.34 to 0.83. Between the adult populations there was moderate genetic
differentiation with an F
ST value of 0.0575, which suggests that the restoration plots had a similar genetic composition to that of the natural population.
The gene flow assessment provides some interesting insights into the genetic diversity of P. cerasoides. In the 16 naturally occurring trees over 83% of the genotyped seed were fathered by unidentified trees whereas in restoration
plot A only about 32% of the pollen came from an unidentified father. This proportion was even less in Plot C where 25% of
the pollen parents were unidentified. The naturally occurring trees within Doi Suthep were surrounded by planted trees, which
were contributing to the paternity of the seed crop. This result demonstrates that ‘‘fill in’’ planting should consist of
locally sourced material if it is considered important to conserve the genetic integrity of the local populations. 相似文献
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Pollen flow from external sources is important for the conservation of tree species in fragmented forests or small populations, because it can be sufficient to prevent differentiation among them, and appears to be able to prevent the loss of their genetic diversity through genetic drift. In this study, we examined the genetic heterogeneity of pollen pools accepted by each Quercus semiserrata seed parent at the Khun Wang Royal Agriculture Research Center, Thailand, both within and among two mast fruiting years (2005 and 2007), using paternity analysis and analysis of molecular variance (AMOVA). The mating systems of the trees were also examined using the multilocus mating system model (MLTR), after determining the genotypes at eight microsatellite loci of 26 seed-trees and 435 seeds from 8 seed-trees in the 2 mast fruiting years. The average distance of effective pollen flow within the plot was estimated to be 52.4 m, and 95% of effective pollen was dispersed within 200 m, indicating that effective pollen flow is highly localized and that most effective pollen is contributed by near-neighbor trees. The proportion of effective pollen that immigrated from external sources was estimated to be 26.2%. The AMOVA analysis based on the pollen haplotypes showed that the pollen pools, both total and for each reproductive year, significantly genetically differed among the seed parents. Using a mixed mating model, the estimate of biparental inbreeding for the total population (tm − ts) was 0.013, indicating that a low proportion of mating occurred among close relatives. The effective number of pollen donors (Nep) was estimated to be 9.987 using the TwoGener model, or 10.989 using the mixed mating model. The effective number of pollen donors of seeds was higher in the mast fruiting year 2005 than in the other examined year, 2007. Consequently the allelic richness and genetic diversity of seeds produced in 2005 were higher than those produced in 2007. Overall, the results show that high outcrossing rates, high levels of gene flow from other populations and heterogeneity in the pollen received by an individual may enhance the ability of populations to maintain effective population sizes. Therefore, these processes may be sufficient to prevent loss of genetic diversity through genetic drift of Q. semiserrata at this study site. 相似文献
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Blakesley David Pakkad Greuk James Celia Torre Franck Elliott Stephen 《New Forests》2004,27(1):89-100
Castanopsis acuminatissima (Bl.) A. DC. is one of a number of framework species which are being planted to restore seasonally dry tropical forests in northern Thailand. This study describes the level of microsatellite variation within and among three populations of this species in three National Parks in northern Thailand: Doi Suthep-Pui, Doi Inthanon and Jae Sawn, using published primers developed for Castanopsis cuspidata var. sieboldii Nakai. The five microsatellite loci employed in this study detected a total of 54 alleles (n = 72). The informativeness of the microsatellite loci varied from six to 18 alleles, with an average of 10.8 alleles found over all loci. The mean observed heterozygosities in the three populations showed no significant deviations from Hardy-Weinberg expectations. The vast majority of genetic diversity was contained within the populations, with no significant differentiation between them (FST = 0.006). Algorithms were designed to capture microsatellite diversity, and the rationale for using microsatellite markers to inform genetic conservation is discussed. The implications for seed collection of C. acuminatissima for forest restoration are also discussed. 相似文献
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