Mohi Ud Din Atta, Mao Hao-Tian, Khan Ahsin, Raza Muhammad Ali, Ahmed Mukhtar, Yuan Ming, Zhang Zhong-Wei, Yuan Shu, Zhang Huai-Yu, Liu Zheng-Hui, Su Yan-Qiu, Chen Yang-Er
College of Life Science, Sichuan Agricultural University, 625014 Ya'an, China; Key Laboratory of Crop Physiology Ecology and Production Management, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China; National Research Center of Intercropping, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
College of Life Science, Sichuan Agricultural University, 625014 Ya'an, China.
Ecotoxicol Environ Saf. 2023 Jan 1;249:114356. doi: 10.1016/j.ecoenv.2022.114356. Epub 2022 Dec 9.
Lead (Pb) pollution in the soil sub-ecosystem has been a continuously growing problem due to economic development and ever-increasing anthropogenic activities across the world. In this study, the photosynthetic performance and antioxidant capacity of Triticeae cereals (rye, wheat and triticale) were compared to assess the activities of antioxidants, the degree of oxidative damage, photochemical efficiency and the levels of photosynthetic proteins under Pb stress (0.5 mM, 1 mM and 2 mM Pb (NO)). Compared with triticale, Pb treatments imposed severe oxidative damage in rye and wheat. In addition, the highest activity of major antioxidant enzymes (SOD, POD, CAT, and GPX) was also found to be elevated. Triticale accumulated the highest Pb contents in roots. The concentration of mineral ions (Mg, Ca, and K) was also high in its leaves, compared with rye and wheat. Consistently, triticale showed higher photosynthetic activity under Pb stress. Immunoblotting of proteins revealed that rye and wheat have significantly lower levels of D1 (photosystem II subunit A, PsbA) and D2 (photosystem II subunit D, PsbD) proteins, while no obvious decrease was noticed in triticale. The amount of light-harvesting complex II b6 (Lhcb6; CP24) and light-harvesting complex II b5 (Lhcb5; CP26) was significantly increased in rye and wheat. However, the increase in PsbS (photosystem II subunit S) protein only occurred in wheat and triticale exposed to Pb treatment. Taken together, these findings demonstrate that triticale shows higher antioxidant capacity and photosynthetic efficiency than wheat and rye under Pb stress, suggesting that triticale has high tolerance to Pb and could be used as a heavy metal-tolerant plant.
由于全球经济发展和日益增加的人为活动，土壤子生态系统中的铅（Pb）污染问题一直持续加剧。在本研究中，比较了禾本科谷类作物（黑麦、小麦和小黑麦）的光合性能和抗氧化能力，以评估在铅胁迫（0.5 mM、1 mM和2 mM Pb(NO)）下抗氧化剂的活性、氧化损伤程度、光化学效率和光合蛋白水平。与小黑麦相比，铅处理对黑麦和小麦造成了严重的氧化损伤。此外，还发现主要抗氧化酶（超氧化物歧化酶、过氧化物酶、过氧化氢酶和谷胱甘肽过氧化物酶）的最高活性也有所提高。小黑麦根部积累的铅含量最高。与黑麦和小麦相比，其叶片中的矿质离子（Mg、Ca和K）浓度也较高。一致地，小黑麦在铅胁迫下表现出较高的光合活性。蛋白质免疫印迹显示，黑麦和小麦中D1（光系统II亚基A，PsbA）和D2（光系统II亚基D，PsbD）蛋白的水平显著较低，而小黑麦中未观察到明显下降。黑麦和小麦中捕光复合体II b6（Lhcb6；CP24）和捕光复合体II b5（Lhcb5；CP26）的量显著增加。然而，PsbS（光系统II亚基S）蛋白的增加仅发生在接受铅处理的小麦和小黑麦中。综上所述，这些发现表明，在铅胁迫下，小黑麦比小麦和黑麦表现出更高的抗氧化能力和光合效率，这表明小黑麦对铅具有较高的耐受性，可以用作耐重金属植物。
