Regeneration methods affect genetic variation and structure in shortleaf pine (Pinus echinata Mill.) (1998)Raja, R. G., Tauer, C. G., Wittwer, R. F., & Huang, Y. (1998). Regeneration methods affect genetic variation and structure in shortleaf pine (Pinus echinata Mill.). Forest Genetics, 5(3), 171-178. Retrieved from https://www.srs.fs.usda.gov/pubs/ja/ja_raja001.pdf The effects of regene ration methods on genetic diversity and structure in shortleaf pine (Pinus echinata Mill.) were examined by quantifying the changes in genetic composition of shortleaf pine stands following harvest by monitoring changes in allele number and frequency at heterozygous loci over time. The results were also compared to the genetic composition ofseed used for artificial regeneration following clear-cutting. Both natural regeneration treatments resulted in higher genetic variation in post-treatment seed, indicating a richer pollen cloud after management. Artificial regeneration showed fewer alleles per locus and fewer polymorphic loci compared to both natural regeneration treatments. Frequency of alternate alleles increased at 13 loci in the seedtree stand after treatment, which is an indication of less inbreeding or consanguineous mating. Single tree selection resulted in an increase in alternate allele frequencies at 9 loci and at 1 loci alternate allele frequencies decreased, indicating that the treatment may result in more inbreeding than seed tree. Artificial regeneration showed a considerable increase in alternate allele frequencies at 16 loci and hence can be considered outbred. The above mentioned observations were confirmed by comparing Ho, He, and F values for the two stands before and after treatment. The seed tree method resulted in a decrease in inbreeding, whereas the first selection cut for single tree selection did not alter it. Artificial regeneration showed a negative F value indicative of high levels of heterozygosity and outbreeding. The natural regeneration treatments did not result in genetic drift whereas the artificial regeneration showed considerable change in the genetic composition of the potential regeneration
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