Phenotypic plasticity and genetic diversity elucidate rarity and vulnerability of an endangered riparian plant
Phenotypic plasticity and genetic diversity elucidate rarity and vulnerability of an endangered riparian plant
复制标题
DOI：
10.1002/ecs2.3996
复制
发表时间：
2022-04-01
期刊：
影响因子：
2.7
通讯作者：
Brzyski, Jessica
中科院分区：
文献类型：
--
作者：
Boyd, Jennifer Nagel;Odell, Jared;Brzyski, Jessica
人类活动加速了环境变化，威胁到许多物种，对稀有物种来说尤其具有挑战性，因为它们相对于更常见的物种而言，迁移和适应能力可能有限。通过表型可塑性的适应能力可以提供一个重要的途径，物种的持久性，在面对这样的变化。我们调查了美国田纳西州东南部一个高度动态的河岸栖息地特有的濒危植物物种及其最广泛的同源物对环境变化的反应，以阐明它们的现状和未来的脆弱性。具体来说，我们比较了人口和物种水平的可塑性，罕见的Pityopsis ruthii和常见的P. graminifolia对比光，温度和水分条件下的生长室实验，以评估其适应环境变化的潜力。与我们的预期相反，P. ruthii比其常见的同源物具有更大的表型可塑性，以应对光照和水分的变化。但这种可塑性与适应性的增加无关，这表明它不是适应性的。同时，我们对这些个体在9个中性微卫星位点进行基因分型，以对比每个物种范围内的遗传多样性。正如预期的那样，P. ruthii相对于其更常见的同源物表现出减少的遗传多样性。总体而言，我们的研究结果雅阁P. ruthii的狭窄范围和当前栖息地特异性，特别是其对高度可变的水分的耐受性，并强调其对未来环境变化的潜在脆弱性。
Environmental change, accelerated by anthropogenic activities, threatens many species and can be especially challenging for rare species given their potentially limited capacity for migration and adaptation relative to more common species. The ability to acclimate via phenotypic plasticity could provide an important path to species persistence in the face of such change. We investigated the responses of an endangered plant species endemic to a highly dynamic riparian habitat in southeastern Tennessee, USA, and its most widespread congener to environmental change to elucidate their current statuses and future vulnerability. Specifically, we compared the population- and species-level plasticity of rare Pityopsis ruthii and common P. graminifolia to contrasting light, temperature, and water conditions in a growth chamber experiment to evaluate their potential to acclimate to environmental change. Contrary to our expectations, P. ruthii had greater phenotypic plasticity than its common congener in response to both altered light and water availability. But this plasticity was not associated with increased fitness, suggesting that it was not adaptive. Concurrently, we genotyped these individuals at nine putatively neutral microsatellite loci to contrast genetic diversity across the range of each species. As expected, P. ruthii exhibited reduced genetic diversity relative to its more common congener. Overall, our findings accord with the narrow range and current habitat specificity of P. ruthii, especially its tolerance of highly variable water, and highlight its potential vulnerability to future environmental change.