Abstract

In plants, long-distance dispersal is both attenuated and directed by specific movement vectors, including animals, wind, and/or water. Hence, movement vectors partly shape metapopulation genetic patterns that are, however, also influenced by other life-history traits such as clonal growth. We studied the relationship between area, isolation, plant-species richness, reproduction, and dispersal mechanisms with genetic diversity and divergence in 4 widespread wetland plant-species in a total of 20 island-like kettle-hole habitats surrounded by an intensive agricultural landscape. Our results showed that genetic parameters reflect the reproduction strategies with the highest genetic diversity being observed in the non-clonal, outcrossing Oenanthe aquatica compared to the clonal Lycopus europaeus, Typha latifolia, and Phragmites australis. Lycopus showed a positive relationship between genetic diversity and kettle-hole area, but a negative relationship with the number of neighboring kettle holes (less isolation). Genetic diversity increased with plant-species richness in the clonal species Phragmites and Lycopus; while it decreased in the non-clonal Oenanthe. Finally, genetic divergence and, therefore, connectivity differed between alternative dispersal strategies, where wind-dispersed Typha and Phragmites had a higher gene flow between the analyzed kettle holes compared with the insect-pollinated, hydrochorous Lycopus and Oenanthe. Our study provides information on genetic patterns related to reproduction and dispersal mechanisms of 4 common wetland species contributing to the understanding of the functioning of plant metacommunities occurring in kettle holes embedded in agricultural landscapes.

中文翻译：

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湿地岛生境中不同克隆性和扩散机制的植物物种的遗传多样性和连通性

摘要

在植物中，长距离传播受到特定运动矢量的减弱和引导，包括动物、风和/或水。因此，运动载体部分地塑造了群体遗传模式，然而，这些遗传模式也受到其他生活史特征的影响，如克隆生长。我们研究了 4 个广泛分布的湿地植物物种的面积、隔离、植物物种丰富度、繁殖和传播机制与遗传多样性和差异之间的关系，这些物种在总共 20 个被集约化农业景观包围的岛状壶穴栖息地中。我们的结果表明，遗传参数反映了与无性系Lycopus europaeus相比，在非克隆性异交Oenanthe Aquatica 中观察到的具有最高遗传多样性的繁殖策略、香蒲和芦苇。Lycopus 的遗传多样性与壶穴面积呈正相关，但与相邻壶穴数量呈负相关（较少隔离）。无性系芦苇和石蒜的遗传多样性随着植物物种丰富度的增加而增加；而它在非克隆Oenanthe 中减少。最后，遗传差异以及其他传播策略之间的连接性不同，与昆虫授粉的水合石蒜相比，风传播的香蒲和芦苇在分析的壶穴之间具有更高的基因流和奥南特。我们的研究提供了与 4 种常见湿地物种的繁殖和扩散机制相关的遗传模式信息，有助于了解发生在农业景观中的壶穴中的植物元群落的功能。