Grupo de Ecología Evolutiva (ECOEVO), Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica. Universidad Rey Juan Carlos-ESCET, Tulipán s/n. 28933 Móstoles, Madrid, Spain.
Ecotoxicology of Air Pollution, CIEMAT, Avda. Complutense, 40. 28040, Madrid, Spain.
Ann Bot. 2023 Nov 23;132(3):541-552. doi: 10.1093/aob/mcad123.
Within-population genetic and phenotypic variation play a key role in the development of adaptive responses to environmental change. Between-population variation is also an essential element in assessing the evolutionary potential of species in response to changes in environmental conditions. In this context, common garden experiments are a useful tool to separate the genetic and environmental components of phenotypic variation. We aimed to assess within- and between-population phenotypic variation of Lupinus angustifolius L. in terms of its evolutionary potential to adapt to ongoing climate change.
We evaluated populations' phenotypic variation of foliar, phenological and reproductive traits with a common garden experiment. Patterns of functional trait variation were assessed with (1) mixed model analyses and coefficients of variation (CVs) with confidence intervals, (2) principal component analyses (PCAs) and (3) correlations between pairs of traits. Analyses were performed at the population level (four populations) and at the latitude level (grouping pairs of populations located in two latitudinal ranges).
Phenotypic variation had a significant genetic component associated with a latitudinal pattern. (1) Mixed models found lower specific leaf area, advanced flowering phenology and lower seed production of heavier seeds in southern populations, whereas CV analyses showed lower within-latitude variation especially in phenological and reproductive traits in southern populations. (2) PCAs showed a clearer differentiation of phenotypic variation between latitudes than between populations. (3) Correlation analyses showed a greater number of significant correlations between traits in southern populations (25 vs. 13).
Between-population phenotypic variation was determined by contrasting temperature and drought at different latitude and elevation. Southern populations had differential trait values compatible with adaptations to high temperatures and drought. Moreover, they had lower within-population variation and a greater number of trait correlations probably as a result of these limiting conditions, making them more vulnerable to climate change.
种群内的遗传和表型变异在适应环境变化方面起着关键作用。种群间的变异也是评估物种对环境条件变化的进化潜力的重要因素。在这种情况下，田间试验是分离表型变异的遗传和环境成分的有用工具。我们旨在评估 Lupinus angustifolius L. 的种群内和种群间表型变异，以评估其适应持续气候变化的进化潜力。
我们通过田间试验评估了叶片、物候和繁殖性状的种群表型变异。通过（1）混合模型分析和置信区间的变异系数（CVs）、（2）主成分分析（PCAs）和（3）对性状的相关性来评估功能性状变异模式。分析在种群水平（四个种群）和纬度水平（将位于两个纬度范围内的两个种群分组）上进行。
表型变异具有与纬度模式相关的显著遗传成分。（1）混合模型发现，南部种群的比叶面积较小，开花物候提前，种子产量较低，而 CV 分析表明，南部种群的纬度内变异较低，尤其是在物候和繁殖性状方面。（2）PCAs 显示出表型变异在纬度之间的分化比在种群之间更为明显。（3）相关分析表明，南部种群中性状之间的显著相关性数量更多（25 对 13）。
种群间的表型变异是由不同纬度和海拔的温度和干旱决定的。南部种群具有与高温和干旱适应相适应的不同特征值。此外，它们的种群内变异较低，性状相关性数量较多，这可能是由于这些限制条件，使它们更容易受到气候变化的影响。
