Abate Elisa, Azzarà Maria, Trifilò Patrizia
Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy.
Plants (Basel). 2021 Sep 13;10(9):1888. doi: 10.3390/plants10091888.
Increase in severity and frequency of drought events is altering plant community composition, exposing biomes to a higher risk of biodiversity losses. This is exacerbated in the most fragile areas as Mediterranean biome. Thus, identifying plant traits for forecasting species with a high risk of drought-driven mortality is particularly urgent. In the present study, we investigated the drought resistance strategy of two Mediterranean native species: Ard. () and L. () by considering the impact of drought-driven water content decline on plant hydraulics. Well-watered samples of displayed higher leaf and stemsaturated water content and lower shoot biomass than samples, but similar root biomass. In response to drought, showed a conservative water use strategy, as the prompt stomatal closure and leaves shedding suggested. A drought-tolerant mechanism was confirmed in samples. Nevertheless, and showed similar drought-driven plant hydraulic conductance (K) recover ability. Root hydraulic traits played a key role to reach this goal. Relative water content as well as loss of cell rehydration capability and membrane damages, especially of stem and root, were good proxies of drought-driven K decline.
干旱事件的严重程度和频率增加正在改变植物群落组成，使生物群落面临更高的生物多样性丧失风险。在地中海生物群落等最脆弱地区，这种情况更加恶化。因此，识别用于预测有干旱驱动死亡高风险物种的植物性状尤为紧迫。在本研究中，我们通过考虑干旱驱动的水分含量下降对植物水力学的影响，研究了两种地中海本土物种：阿尔德（Ard.）（）和拉（L.）（）的抗旱策略。浇水良好的阿尔德样本比拉样本显示出更高的叶片和茎饱和含水量以及更低的地上生物量，但根系生物量相似。响应干旱时，阿尔德表现出保守的水分利用策略，这从迅速的气孔关闭和叶片脱落可以看出。在拉样本中证实了一种耐旱机制。然而，阿尔德和拉显示出相似的干旱驱动植物水力导度（K）恢复能力。根系水力性状对实现这一目标起关键作用。相对含水量以及细胞再水化能力的丧失和膜损伤，尤其是茎和根的膜损伤，是干旱驱动的K下降的良好指标。
