Author(s): Valdir Marcos Stefenon | Leonardo Severo da Costa
Journal: Annals of Forest Research
ISSN 1844-8135
Volume: 55;
Issue: 1;
Start page: 3;
Date: 2012;
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Keywords: adaptability | allelic richness | GIS | heterozygosity | inbred mating | inbreeding coefficient.
ABSTRACT
Computer simulations were employed in this study aiming to understandthe effects of repeated cycles of inbred mating in isolated populations of tree species with different effective sizes and over up to 1000 generations. The results revealed a susceptibility of allelic richness to both, population size and repeated generationsunder inbred mating and a low but signifi cant increase of the inbreeding coeffi cient over generations in populations with 50 and 100 plants, but not in populations with500 and 1000 individuals. The loss of alleles occurred throughout all generations and was largely infl uenced by the population size. The most outstanding increase in the inbreeding coeffi cient occurred from the initial generation to the 5th generation, independent of the population size. The comparison of simulated results with data obtained from a fi eld studie corroborated the hypothesis that isolated populations tend to more drastically suffer with loss of alleles and increase of inbreeding coeffi cient, while continuous forests, with effective production of fertile seeds and regenerationof seedlings, are inclined to preserve comparatively higher allelic richness and lower inbreeding coeffi cient over generations. In general, the results obtained highlight the importance of special care in selecting ESUs and preserving isolated populations, towards the conservation of forest genetic resources and adapatedness preservation.
Journal: Annals of Forest Research
ISSN 1844-8135
Volume: 55;
Issue: 1;
Start page: 3;
Date: 2012;
VIEW PDF
DOWNLOAD PDF Original pageKeywords: adaptability | allelic richness | GIS | heterozygosity | inbred mating | inbreeding coefficient.
ABSTRACT
Computer simulations were employed in this study aiming to understandthe effects of repeated cycles of inbred mating in isolated populations of tree species with different effective sizes and over up to 1000 generations. The results revealed a susceptibility of allelic richness to both, population size and repeated generationsunder inbred mating and a low but signifi cant increase of the inbreeding coeffi cient over generations in populations with 50 and 100 plants, but not in populations with500 and 1000 individuals. The loss of alleles occurred throughout all generations and was largely infl uenced by the population size. The most outstanding increase in the inbreeding coeffi cient occurred from the initial generation to the 5th generation, independent of the population size. The comparison of simulated results with data obtained from a fi eld studie corroborated the hypothesis that isolated populations tend to more drastically suffer with loss of alleles and increase of inbreeding coeffi cient, while continuous forests, with effective production of fertile seeds and regenerationof seedlings, are inclined to preserve comparatively higher allelic richness and lower inbreeding coeffi cient over generations. In general, the results obtained highlight the importance of special care in selecting ESUs and preserving isolated populations, towards the conservation of forest genetic resources and adapatedness preservation.
