Pepe Maria, Crescente Maria Fiore, Varone Laura
Department of Environmental Biology, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy.
Plants (Basel). 2022 Mar 28;11(7):899. doi: 10.3390/plants11070899.
Invasive alien species (IAS) are a problem, especially in drought-prone environments such as the Mediterranean Basin where the exacerbation of the already severe conditions could constrain the native species acclimatation degree, creating new opportunities for IAS. Climate change may drive IAS expansions, even if different IAS can vary in their acclimatation response. Thus, it is important to obtain a broader insight of how the different IAS face abiotic stress. This research aimed to compare the effect of the imposed water stress on physiological and morphological leaf traits of (AA), (RP), and (PA), which are widely spread IAS in the Mediterranean Basin. Our results showed a species-dependent effect of the water stress at a physiological and morphological level, as well as an interaction between species and stress duration. Despite a common strategy characterized by low stomatal control of the photosynthesis, AA, PA, and RP differ in their sensitivity to water stress. In particular, even if AA was characterized by a more water-spending strategy, it was more resistant to water stress than PA and RP. In this view, the key factor was its plasticity to increase leaf mass per area (LMA) in response to water stress.
外来入侵物种是一个问题，特别是在地中海盆地等易干旱的环境中，那里本就严峻的条件进一步恶化可能会限制本地物种的适应程度，为外来入侵物种创造新的机会。气候变化可能会推动外来入侵物种的扩张，即使不同的外来入侵物种在适应反应上可能存在差异。因此，更全面地了解不同的外来入侵物种如何应对非生物胁迫非常重要。本研究旨在比较施加水分胁迫对意大利苍耳（AA）、假高粱（RP）和豚草（PA）叶片生理和形态特征的影响，这三种植物是在地中海盆地广泛分布的外来入侵物种。我们的结果表明，水分胁迫在生理和形态水平上具有物种依赖性效应，以及物种与胁迫持续时间之间的相互作用。尽管这三种植物都有以低气孔控制光合作用为特征的共同策略，但意大利苍耳、豚草和假高粱对水分胁迫的敏感性不同。特别是，即使意大利苍耳具有更耗水的策略，但它比豚草和假高粱更耐水分胁迫。从这个角度来看，关键因素是其响应水分胁迫增加单位面积叶质量（LMA）的可塑性。
