Background
Small populations are predominantly vulnerable to inbreeding and inbreeding depression (ID). Owing to increased levels of inbreeding on individuals in small populations, ID could decrease the population growth rate, as well as its effective size, and exacerbate the extinction risk. Inbreeding depression remains a crucial area of research in conservation biology, ecology, and evolutionary biology. This study aims to elucidate the reproductive biology, inbreeding, and ID of Paeonia decomposita and to conserve, manage, and improve them better in the future.

Results
Paeonia decomposita belongs to a xenogamous category and is partially self-compatible; moreover, it requires pollinators for seed production. Lately, the occurrence of pollination and pollinator limitations has affected the seed set. Low seed set primarily correlated with an abnormality of meiosis in the pollen mother cell, moderate to low genetic diversity, drought and extreme weather, pollinator limitation, or carpel space limit. One of the primary reasons for endangered mechanism in P. decomposita is the low seed set under natural conditions. The cumulative value of ID was positive, and outcrossed progeny outperformed selfed progeny.

Conclusions
Paeonia decomposita requires pollinators to ensure seed production either through autogamy, geitonogamy, or allogamy. It is both allogamous and partially self-compatible, as well as a successful outcrosser. Inbreeding occurs frequently and results in ID, which imposes a potential threat to the survival of populations. Besides, it needs conservation via in situ and natural return methods.



中文翻译：

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濒临灭绝的Pa药 Paeonia decomposita （Paeoniaceae）的近交和近交凹陷

背景信息
人口很少主要是近亲和近亲抑郁症（ID）。由于小种群个体近交的水平增加，ID可能会降低种群的增长率及其有效规模，并加剧灭绝的风险。近亲抑郁仍然是保护生物学，生态学和进化生物学研究的关键领域。这项研究旨在阐明of 药 的生殖生物学，近亲繁殖和ID ，并在将来更好地保护，管理和改善它们。

结果
Pa药分解 属于异种类别，部分自相容；此外，它需要传粉媒介进行种子生产。最近，授粉和授粉限制的发生影响了种子结实。种子集数低主要与花粉母细胞减数分裂异常，中低遗传多样性，干旱和极端天气，授粉媒介限制或心皮空间限制有关。 腐烂假单胞菌的 危险机制的主要原因之一 是自然条件下结实率低。ID的累积值为正，并且杂交后代的表现优于自交后代。

结论
Pa药Pa药 要求传粉者通过同性，异基因或同种异体来确保种子生产。它是同构的，部分自相容的，也是成功的异国情调。近亲繁殖经常发生，并导致ID，这对种群的生存构成了潜在的威胁。此外，还需要通过原位和 自然归还 方法进行保护。