Genetic rescue persists beyond first-generation outbreeding in small populations of a rare plant
Genetic rescue persists beyond first-generation outbreeding in small populations of a rare plant
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稀有植物小种群中的基因拯救超越了第一代近交繁殖
DOI：
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发表时间：
2007
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影响因子：
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通讯作者：
M. Fischer
中科院分区：
文献类型：
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作者：
Y. Willi;M. Kleunen;S. Dietrich;M. Fischer
栖息地破碎化通常会导致遗传问题，并在种群变小时降低适应性。在小种群中放养来自其他种群的个体可能会丰富遗传变异并减轻近亲繁殖，但由于潜在的远系繁殖衰退，这种人工基因流动在保护中并不常用。研究了长期种群规模、种群间遗传距离和试验环境对毛茛（Ranunculus reptans L.）种群间远缘杂交对个体的总体适应度有积极的影响，种群间杂种的适应度优势在第二代后代（F2）中得以保持。小种群从种群间远系繁殖中受益更大。杂交群体之间在中性标记或数量性状上的遗传距离并不重要。这些结果在接近自然的无竞争和竞争条件下是一致的。我们的结论是，种群间远系繁殖的好处可能超过潜在的缺点，特别是对遭受近亲繁殖的种群。
Habitat fragmentation commonly causes genetic problems and reduced fitness when populations become small. Stocking small populations with individuals from other populations may enrich genetic variation and alleviate inbreeding, but such artificial gene flow is not commonly used in conservation owing to potential outbreeding depression. We addressed the role of long-term population size, genetic distance between populations and test environment for the performance of two generations of offspring from between-population crosses of the locally rare plant Ranunculus reptans L. Interpopulation outbreeding positively affected an aggregate measure of fitness, and the fitness superiority of interpopulation hybrids was maintained in the second offspring (F2) generation. Small populations benefited more strongly from interpopulation outbreeding. Genetic distance between crossed populations in neutral markers or quantitative characters was not important. These results were consistent under near-natural competition-free and competitive conditions. We conclude that the benefits of interpopulation outbreeding are likely to outweigh potential drawbacks, especially for populations that suffer from inbreeding.