已知大气CO2浓度升高会影响许多植物在干旱下的反应。本文旨在测量叶片气体交换,用水效率,羧化效率,在渐进干旱条件下曼陀罗的光系统II(PSII)活性,以及400ppm(aCO2)的环境条件和700ppm(eCO2)的升高条件。在实验室生长室中,在100%和60%的田间容量下,在400ppm和700ppm下生长。每隔两天10天,光合作用速率,气孔导度,蒸腾速率,细胞间CO2浓度,用水效率,内在用水效率,瞬时羧化效率,PSII活动,电子输运速率,和光化学猝灭进行了测量。虽然干旱胁迫通常对D.stramonium的上述生理性状有负面影响,发现eCO2浓度减轻了干旱的不利影响,并且与aCO2相比,大多数生理参数随干旱持续时间的增加而持续。D.斯特拉米,它是在干旱条件下生长的,在第8天重新浇水,表明除最大荧光外的所有参数均部分恢复,与aCO2相比,eCO2的回收率更高。这些结果表明,升高的二氧化碳可以减轻干旱对生长的不利影响,从而通过提高其水分利用效率来增强该杂草的适应机制。结论是,这种杂草有可能通过提高其与干旱易发地区其他植物的竞争力来利用气候变化,这表明它可以扩展到新的地方。
Rising atmospheric CO2 concentrations are known to influence the response of many plants under drought. This paper aimed to measure the leaf gas exchange, water use efficiency, carboxylation efficiency, and photosystem II (PS II) activity of Datura stramonium under progressive drought conditions, along with ambient conditions of 400 ppm (aCO2) and elevated conditions of 700 ppm (eCO2). Plants of D. stramonium were grown at 400 ppm and 700 ppm under 100 and 60% field capacity in a laboratory growth chamber. For 10 days at two-day intervals, photosynthesis rate, stomatal conductance, transpiration rate, intercellular CO2 concentration, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, PSII activity, electron transport rate, and photochemical quenching were measured. While drought stress had generally negative effects on the aforementioned physiological traits of D. stramonium, it was found that eCO2 concentration mitigated the adverse effects of drought and most of the physiological parameters were sustained with increasing drought duration when compared to that with aCO2. D. stramonium, which was grown under drought conditions, was re-watered on day 8 and indicated a partial recovery in all the parameters except maximum fluorescence, with this recovery being higher with eCO2 compared to aCO2. These results suggest that elevated CO2 mitigates the adverse growth effects of drought, thereby enhancing the adaptive mechanism of this weed by improving its water use efficiency. It is concluded that this weed has the potential to take advantage of climate change by increasing its competitiveness with other plants in drought-prone areas, suggesting that it could expand into new localities.