Division of Environment Science, Indian Agricultural Research Institute, New Delhi, India.
Department of Environmental Sciences, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India.
Int J Biometeorol. 2024 May;68(5):991-1004. doi: 10.1007/s00484-024-02642-4. Epub 2024 Mar 25.
An experimental study was conducted to assess the detrimental effect of ground-level ozone (O) on garlic physiology and to find out appropriate control measures against ground-level O, at TNAU-Horticultural Research farm, Udhagamandalam. Elevated ground ozone levels significantly decreased garlic leaf chlorophyll, photosynthetic rate, stomatal conductance, total soluble solids and pungency. The garlic chlorophyll content was highest in ambient ozone level and lowest in elevated ozone@200 ppb, highest stomatal conductance was recorded in ambient ozone with foliar spray of 3%Panchagavya, and the lowest was observed in elevated ozone@200 ppb. Since the elevated O had reduced in garlic photosynthetic rate significantly the lowest was observed in elevated O@200 ppb and the highest photosynthetic rate was observed in ambient Ozone with foliar spray 3% of panchagavya after a week. The antioxidant enzymes of garlic were increased with increased concentration of tropospheric ozone. The highest catalase (60.97 µg of HO/g of leaf) and peroxidase (9.13 ΔA/min/g of leaf) concentration was observed at 200 ppb elevated ozone level. Garlic pungency content was highest in ambient ozone with foliar spray of 0.1% ascorbic acid and the lowest was observed under elevated O@200 ppb. Highest total soluble solids were observed in ambient ozone with foliar spray of 3%Panchagavya and the lowest observed in elevated ozone@200 ppb. Thus, tropospheric ozone has a detrimental impact on the physiology of crops, which reduced crop growth and yield. Under elevated O levels, ascorbic acid performed well followed by panchagavya and neem oil. The antioxidant such as catalase and peroxidase had positive correlation among themselves and had negative correlation with chlorophyll content, stomatal conductance, photosynthetic rate, pungency and TSS. The photosynthetic rate has high positive correlation with chlorophyll content, pungency and TSS. Correlation analysis confirmed the negative effects of tropospheric ozone and garlic gas exchange parameters and clove quality. The ozone protectants will reduce stomatal opening by which the entry of O in to the cell will be restricted and other hand they also will alleviate ROS and allied stresses.
一项实验研究在 TNAU-园艺研究农场进行，以评估地面臭氧（O）对大蒜生理学的有害影响，并找出针对地面 O 的适当控制措施。升高的地面臭氧水平显著降低了大蒜叶片中的叶绿素、光合速率、气孔导度、总可溶性固体和辣味。在环境臭氧水平下，大蒜叶绿素含量最高，在升高的臭氧@200 ppb 下含量最低，在环境臭氧下用 3%的 Panchagavya 喷雾处理的气孔导度最高，在升高的臭氧@200 ppb 下最低。由于升高的 O 显著降低了大蒜的光合速率，因此在升高的 O@200 ppb 下观察到最低的光合速率，而在环境臭氧下用 3%的 Panchagavya 喷雾处理一周后观察到最高的光合速率。大蒜的抗氧化酶随着对流层臭氧浓度的增加而增加。在 200 ppb 升高的臭氧水平下，观察到最高的过氧化氢酶（60.97µg 的 HO/g 的叶）和过氧化物酶（9.13ΔA/min/g 的叶）浓度。在环境臭氧下用 0.1%的抗坏血酸喷雾处理的大蒜辣味含量最高，而在升高的 O@200 ppb 下观察到最低的辣味含量。在环境臭氧下用 3%的 Panchagavya 喷雾处理的总可溶性固体含量最高，在升高的臭氧@200 ppb 下观察到最低的总可溶性固体含量。因此，对流层臭氧对作物的生理学有不利影响，这会降低作物的生长和产量。在升高的 O 水平下，抗坏血酸、Panchagavya 和印楝油的效果都很好。抗氧化剂如过氧化氢酶和过氧化物酶之间存在正相关，与叶绿素含量、气孔导度、光合速率、辣味和 TSS 之间存在负相关。光合速率与叶绿素含量、辣味和 TSS 之间存在高度正相关。相关分析证实了对流层臭氧对大蒜气体交换参数和丁香质量的负面影响。臭氧保护剂将通过限制 O 进入细胞的开口来减少气孔的打开，另一方面，它们还将减轻 ROS 和相关的压力。
