PREMISE Newly formed polyploids face significant obstacles to persistence and population establishment because of fitness costs of intercytotype mating. Selfing provides the opportunity to escape mate limitation, enabling production of new individuals and increasing the likelihood of fixation of new polyploid lineages. Still, association between self-compatibility and polyploidy is not always clear. We compared self-incompatibility and inbreeding depression in neotetraploids and their diploid progenitor to explore the direct effects of whole genome duplications on self-incompatibility and the implications of ploidy-driven changes for polyploid establishment. METHODS Outcross and self-pollinations were performed in diploids and synthetic neotetraploids of Jasione maritima var. maritima, and reproductive success was measured through fruit and seed production and seed germination. Self- and outcross offspring were grown under controlled conditions, and plant performance was measured through several fitness parameters. RESULTS Neotetraploids showed an overall lower performance than diploids. Reproductive success was negatively affected by selfing in both cytotypes. However, greater variation in the expression of self-incompatibility was observed in neotetraploids; additionally, developmental and physiological parameters were not affected by selfing on neotetraploids, with an overall similar fitness of outcrossed and selfed individuals, resulting in lower inbreeding depression indexes. CONCLUSIONS Neotetraploids might have benefited from selfing at initial stages after their formation. Genome duplications resulted in leaky self-incompatibility, enabling the production of offspring under minority cytotype disadvantage with similar fitness as outcrossed offspring. Our results support theoretical assumptions that selfing might be important for neopolyploid establishment, although changes in self-incompatibility might not be abrupt.

中文翻译：

---

自交是促进多倍体建立的生殖保证吗？新四倍体的适应性降低、自交不亲和性降低和近交抑制降低

前提 由于细胞间型交配的适应性成本，新形成的多倍体在持久性和种群建立方面面临重大障碍。自交提供了摆脱配偶限制的机会，能够产生新个体并增加固定新多倍体谱系的可能性。尽管如此，自亲和多倍体之间的关联并不总是很清楚。我们比较了新四倍体及其二倍体祖先的自交不亲和和近交抑制，以探索全基因组重复对自交不亲和的直接影响以及倍性驱动的变化对多倍体建立的影响。方法 在 Jasione maritima var. 的二倍体和合成新四倍体中进行异交和自花授粉。海事，繁殖成功率通过果实和种子生产以及种子发芽来衡量。自交和异交后代在受控条件下生长，并通过几个适合度参数测量植物性能。结果 新四倍体的总体性能低于二倍体。两种细胞型的自交都会对生殖成功产生负面影响。然而，在新四倍体中观察到自交不亲和表达的更大变化。此外，发育和生理参数不受新四倍体自交的影响，异交和自交个体的整体适应性相似，导致近交抑制指数较低。结论 新四倍体可能在形成后的初始阶段受益于自交。基因组重复导致泄漏的自我不相容性，从而能够在少数细胞型劣势下产生具有与异型后代相似的适应性的后代。我们的结果支持自交可能对新多倍体建立很重要的理论假设，尽管自交不亲和的变化可能不会突然发生。