Colonization is a critical filter, setting the stage for short‐term and long‐term population success. Increased propagule pressure (e.g., more founding individuals) usually enhances colonization; however, this pattern may be driven by purely numeric effects, population genetic diversity effects, or both. To determine the independent and interactive effects of propagule pressure and genetic diversity, we conducted a seed addition experiment in the field using the ruderal annual Arabidopsis thaliana. Propagule pressure treatments spanned five levels, from 32 to 960 seeds per 0.25‐m² plot. Founder populations were composed of one, four, or eight genotypes and exposed to ambient or reduced levels of interspecific competition. Genotype monocultures were included to quantify additive vs. non‐additive effects. Populations were followed for three generations, with abundance, population persistence and genotype retention (the proportion of introduced genotypes persisting over time) as the major response variables. Increased propagule pressure enhanced abundance immediately following introduction, particularly where nutrient availability was high and competition reduced. Greater propagule pressure also increased the likelihood of population persistence and genotype retention through three generations. However, most populations experienced rapid abundance declines over time, yielding no relationship between propagule pressure and third‐generation abundance across persisting populations. Under reduced competition, increased genetic diversity led to a marginal increase in persistence through the third generation that was more pronounced, and statistically significant, in low nutrient conditions. Genetic diversity did not affect persistence through the first generation, thus indicating that genetic diversity effects strengthened over time. Nevertheless, genotypic mixture populations fell short of expectations based on performance in monocultures (negative non‐additive effects). Increased genetic diversity was also associated with abundance declines, largely due to one particularly high‐performing genotype in the lowest diversity treatments (i.e., genotypic identity effects). Overall, our results indicate that increases in both propagule pressure and genetic diversity can enhance colonization success but are highly context dependent. They also highlight novel ways in which both factors can impact the retention of introduced genetic diversity over time. Our findings pinpoint the determinants of a fundamental population process and have key implications for applications where enhanced or suppressed colonization is desired, including ecological restoration and invasive species management.

中文翻译：

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繁殖压力和遗传多样性增强了rud属物种的定殖：多代野外实验

殖民化是一个至关重要的过滤器，为短期和长期的种群成功奠定了基础。繁殖压力的增加（例如，更多的创始个体）通常会增强定植。但是，这种模式可能是由纯粹的数字效应，种群遗传多样性效应或两者共同驱动的。为了确定繁殖体压力和遗传多样性的独立和交互作用，我们在野外使用了一年生的拟南芥进行了种子添加实验。传播压力处理跨越五个级别，每0.25-m ²从32到960种子阴谋。建立者群体由一种，四种或八种基因型组成，暴露于环境中或种间竞争水平降低。基因型单培养被包括在内，以量化加性与非加性作用。追踪种群三代，其中主要变量为丰度，种群持久性和基因型保留率（引入的基因型随时间推移持续存在的比例）。引入后，繁殖压力的增加会增加丰度，特别是在养分利用率高且竞争减少的情况下。更高的繁殖压力还通过三代人增加了种群持续存在和基因型保留的可能性。但是，随着时间的流逝，大多数人口的丰度迅速下降，在持续存在的人群中，繁殖压力与第三代丰度之间没有关系。在竞争减少的情况下，遗传多样性的增加导致第三代的持久性略有增加，这在低营养条件下更为明显，并且具有统计意义。遗传多样性并没有影响到第一代的持久性，因此表明遗传多样性的影响随着时间的推移而增强。然而，基于单种养殖的表现，基因型混合种群没有达到预期（负非加性效应）。遗传多样性的增加也与丰度的下降有关，这主要是由于在多样性最低的处理中一种表现特别出色的基因型（即基因型同一性效应）。全面的，我们的结果表明，繁殖体压力和遗传多样性的增加均可提高定植成功率，但高度依赖于环境。他们还着重介绍了两个因素都可以随着时间影响引入的遗传多样性的保留的新颖方式。我们的发现查明了基本种群过程的决定因素，并对需要增强或抑制定殖的应用（包括生态恢复和入侵物种管理）具有关键意义。