Laboratory of Air Pollution and Global Climate Change, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
Laboratory of Air Pollution and Global Climate Change, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
Sci Total Environ. 2023 Sep 1;889:164275. doi: 10.1016/j.scitotenv.2023.164275. Epub 2023 May 19.
The multifunctionality of plants is well known to be compromised in the areas experiencing higher concentrations of tropospheric ozone (O). Mango (Mangifera indica L.) cultivation is essential to the economy of tropical regions, including India. Mango, widely grown in suburban and rural areas, experiences production loss due to air pollutants. Ozone, the most important phytotoxic gas in mango growing areas, warrants an investigation of its effects. Therefore, we assessed the differential sensitivity of mango saplings (two-year-old hybrid and regular-bearing mango varieties, Amrapali and Mallika) at two levels of O: ambient and elevated (ambient + 20 ppb) using open-top chambers from September 2020 to July 2022. Under elevated O, both varieties showed similar seasonal responses (winter and summer) for all the growth parameters but differed in their height-diameter allocation pattern. A decrease in stem diameter and an increase in plant height were observed in Amrapali, whereas Mallika showed a reverse response. Early emergence of phenophases was noticed during the reproductive growth of both varieties under elevated O exposure. However, these changes were more pronounced in Amrapali. Stomatal conductance was more negatively affected in Amrapali than in Mallika under elevated O during both seasons. Furthermore, leaf morpho-physiological traits (leaf nitrogen concentration, leaf area, leaf mass per area, and photosynthetic nitrogen use efficiency) and inflorescence parameters responded variably in both varieties under elevated O stress. A decrease in photosynthetic nitrogen use efficiency, further enhanced yield loss which was more pronounced in Mallika than in Amrapali under elevated O exposure. The results of this study could be useful in selecting a better-performing variety based on its productivity, which will be economically more beneficial in achieving the goal of sustainable production at the anticipated high O levels under a climate change scenario.
植物的多功能性在经历对流层臭氧（O）浓度较高的地区受到损害，这是众所周知的。芒果（Mangifera indica L.）种植对包括印度在内的热带地区的经济至关重要。由于空气污染物，广泛种植在郊区和农村地区的芒果会遭受减产。臭氧是芒果种植区最重要的植物毒性气体，因此需要对其影响进行调查。因此，我们使用开顶式气室在两个臭氧水平（环境和升高（环境+20 ppb））下评估了两年生杂交和常规结实芒果品种（Amrapali 和 Mallika）的芒果幼苗的差异敏感性，时间为 2020 年 9 月至 2022 年 7 月。在升高的 O 下，两种品种的所有生长参数都表现出相似的季节性反应（冬季和夏季），但在高度-直径分配模式上有所不同。在 Amrapali 中观察到茎直径减小和株高增加，而 Mallika 则表现出相反的反应。在两种品种的生殖生长过程中，都观察到了酚相的早期出现，在升高的 O 暴露下，这种情况更为明显。然而，在 Amrapali 中，这些变化更为明显。在两个季节，在升高的 O 下，Amrapali 的气孔导度比 Mallika 受到更负面的影响。此外，叶片形态生理特性（叶片氮浓度、叶面积、叶质量/面积和光合氮利用效率）和花序参数在升高的 O 胁迫下，两种品种的反应各不相同。光合氮利用效率的降低进一步加剧了产量损失，在升高的 O 暴露下，Mallika 的损失比 Amrapali 更为明显。本研究的结果可用于根据其生产力选择表现更好的品种，这在实现气候变化情景下预期的高 O 水平下可持续生产的目标方面具有经济上的优势。
