Influence of inbreeding depression on a lake population of Nymphoides peltata after restoration from the soil seed bank
Influence of inbreeding depression on a lake population of Nymphoides peltata after restoration from the soil seed bank
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DOI：
10.1007/s10592-005-9107-4
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发表时间：
2006-02
影响因子：
2.2
通讯作者：
S. Takagawa;I. Washitani;R. Uesugi;Y. Tsumura
中科院分区：
文献类型：
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作者：
S. Takagawa;I. Washitani;R. Uesugi;Y. Tsumura
如果在退化的生境中再生过程受到高度限制，那么在恢复努力之后，近亲繁殖衰退对支离破碎的小种群的负面影响可能会表现得更强烈。研究了近交衰退对从残留土壤种子库中恢复的菜种群的潜在影响。人工授粉实验表明，一个单一的剩余的同型花柱基因的自交亲和性和显着的自交后代的近交衰退，特别是在相关的幼苗生长参数（$$\updelta=0.5$$-0.6的生物量，和$$\updelta=0.3$$-0.4的相对生长速度）。遗传分析表明，目前土壤种子库中的亲本数量仅为2-8个，且在3个采样点均以单一的同胞家系为主。结果还表明，同型基因的自交后代在两个位点上均占绝对优势（86.8%和94.7%）。结果，种子库幼苗的生长性能显著降低，至与自交后代一样低的水平。建议采取积极的恢复措施，尽量减少遗传瓶颈的负面影响，并根据遗传和人口统计学研究进行持续监测。
The negative effects of inbreeding depression on fragmented small populations are likely to be expressed more strongly after restoration efforts if regeneration processes have been highly restricted in degraded habitats. We examined the potential influences of inbreeding depression on a population ofNymphoides peltata(Menyanthaceae) restored from the remnant soil seed bank. A hand-pollination experiment demonstrated self-compatibility of a single remaining homostyle genet and significant inbreeding depression in selfed progeny, especially in parameters related to seedling growth ($$\updelta=0.5$$–0.6 for biomass, and $$\updelta=0.3$$–0.4 for relative growth rate). Our genetic analysis indicated that the presumed number of parents contributing to the current soil seed bank was only 2–8 genets and that a single sib-family dominated at each of three sampling sites. The results also showed that the selfed progeny of the homostyle genet were overwhelmingly dominant at two sites (86.8 and 94.7%). As a result, the growth performance of the seed bank seedlings was significantly reduced, to a level as low as that of the selfed progeny. Active restoration efforts to minimize the negative effects of the genetic bottleneck and continuous monitoring based on genetic and demographic study are recommended.