Departamento de Ecología, Center of Applied Ecology and Sustainability (CAPES), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile; Instituto Milenio en Socio-Ecología Costera (SECOS), Santiago, Chile; Facultad de Artes Liberales, Universidad Adolfo Ibáñez, Santiago, Chile.
Departamento de Ecología, Center of Applied Ecology and Sustainability (CAPES), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile.
Comp Biochem Physiol A Mol Integr Physiol. 2023 May;279:111388. doi: 10.1016/j.cbpa.2023.111388. Epub 2023 Feb 4.
The success of biological invasions ultimately relies on phenotypic traits of the invasive species. Aphids, which include many important pests worldwide, may have been successful invading new environments partly because they can maximize reproductive output by becoming parthenogenetic and losing the sexual phase of their reproductive cycle. However, invasive populations of aphids invading wide ranges can face contrasting environmental conditions and requiring different phenotypic strategies. Besides transitions in their reproductive cycle, it is only partially known which phenotypic traits might be associated to the invasion success of aphid populations in extended novel ranges. Here, we used four genotypes of the pea aphid Acyrthosiphon pisum from two localities in Chile to test for phenotypic specialization that might explain their establishment and spread in habitats exhibiting contrasting environmental conditions. We show that lineages living at a higher latitude with low temperatures show, in addition to facultative sexual reproduction, smaller body sizes, lower metabolic rates and a higher tolerance to the cold than the obligate asexual lineages living in a mild weather, at the expense of fecundity. Conversely, at higher temperatures only asexual lineages were found, which exhibit larger body sizes, higher reproductive outputs and consequently enhanced demographic ability. As a result, in conjunction with the reproductive mode, lineage specialization in physiological and life-history traits could be taken into account as an important strategy for populations of pea aphid to effectively invade extended novel ranges comprising different climatic conditions.
生物入侵的成功最终依赖于入侵物种的表型特征。蚜虫包括世界上许多重要的害虫，它们可能成功地入侵新环境，部分原因是它们可以通过孤雌生殖和失去生殖周期的有性阶段来最大限度地提高繁殖产量。然而，广泛入侵的蚜虫种群可能面临着截然不同的环境条件，并需要不同的表型策略。除了生殖周期的转变之外，部分已知的表型特征可能与蚜虫种群在扩展的新范围内的入侵成功有关。在这里，我们使用来自智利两个地点的四种豌豆蚜 Acyrthosiphon pisum 基因型来测试可能解释它们在表现出对比环境条件的栖息地中建立和传播的表型特化。我们表明，生活在高纬度地区、温度较低的谱系除了有条件的有性繁殖外，体型较小、代谢率较低、对寒冷的耐受性较高，而生活在温和天气下的强制性无性谱系则以牺牲繁殖力为代价。相反，只有在较高温度下才发现无性谱系，它们表现出较大的体型、较高的繁殖产量，从而提高了人口能力。因此，与生殖模式相结合，谱系在生理和生活史特征上的特化可以被视为豌豆蚜种群有效入侵包含不同气候条件的扩展新范围的重要策略。
