Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress
The objective of this study was to investigate the effects of Mg and IAA on the photosystems of Al-stressed alfalfa (Medicago sativa L.). Alfalfa seedlings with or without apical buds were exposed to solutions fully mixed with 0 or 100 μM AlCl3 and 0 or 50 μM MgCl2 followed by foliar spray with wate...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-06-01
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| Series: | Frontiers in Plant Science |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fpls.2020.00746/full |
| _version_ | 1819012332486918144 |
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| author | Liantai Su Aimin Lv Wuwu Wen Peng Zhou Yuan An Yuan An |
| author_facet | Liantai Su Aimin Lv Wuwu Wen Peng Zhou Yuan An Yuan An |
| author_sort | Liantai Su |
| collection | DOAJ |
| description | The objective of this study was to investigate the effects of Mg and IAA on the photosystems of Al-stressed alfalfa (Medicago sativa L.). Alfalfa seedlings with or without apical buds were exposed to solutions fully mixed with 0 or 100 μM AlCl3 and 0 or 50 μM MgCl2 followed by foliar spray with water or IAA. Results from seedlings with apical buds showed that application of Mg and IAA either alone or combine greatly alleviated the Al-induced damage on photosystems. The values of photosynthetic rate (Pn), effective quantum yields [Y(I) and Y(II)] and electron transfer rates (ETRI and ETRII), proton motive force (pmf), cyclic electron flow (CEF), proton efflux rate (gH+), and activities of ATP synthase and PM H+-ATPase significantly increased, and proton gradient (ΔpHpmf) between lumen and stroma decreased under Al stress. After removing apical buds of seedlings, the Y(I), Y(II), ETRI, ETRII, pmf, and gH+ under exogenous spraying IAA significantly increased, and ΔpHpmf significantly decreased in Mg addition than Al treatment alone, but they were no significant difference under none spraying IAA. The interaction of Mg and IAA directly increased quantum yields and electron transfer rates, and decreased O2– accumulation in Al-stressed seedlings with or without apical buds. These results suggest that IAA involves in Mg alleviation of Al-induced photosystem damage via increasing pmf and PM H+-ATPase activity, and decreasing ΔpHpmf. |
| first_indexed | 2024-12-21T01:42:22Z |
| format | Article |
| id | doaj.art-8e0ce3d732e84ca4a4f20afdf0d342b3 |
| institution | Directory Open Access Journal |
| issn | 1664-462X |
| language | English |
| last_indexed | 2024-12-21T01:42:22Z |
| publishDate | 2020-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Plant Science |
| spelling | doaj.art-8e0ce3d732e84ca4a4f20afdf0d342b32022-12-21T19:20:07ZengFrontiers Media S.A.Frontiers in Plant Science1664-462X2020-06-011110.3389/fpls.2020.00746504668Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum StressLiantai Su0Aimin Lv1Wuwu Wen2Peng Zhou3Yuan An4Yuan An5School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, ChinaSchool of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, ChinaSchool of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, ChinaSchool of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, ChinaSchool of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, ChinaKey Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, ChinaThe objective of this study was to investigate the effects of Mg and IAA on the photosystems of Al-stressed alfalfa (Medicago sativa L.). Alfalfa seedlings with or without apical buds were exposed to solutions fully mixed with 0 or 100 μM AlCl3 and 0 or 50 μM MgCl2 followed by foliar spray with water or IAA. Results from seedlings with apical buds showed that application of Mg and IAA either alone or combine greatly alleviated the Al-induced damage on photosystems. The values of photosynthetic rate (Pn), effective quantum yields [Y(I) and Y(II)] and electron transfer rates (ETRI and ETRII), proton motive force (pmf), cyclic electron flow (CEF), proton efflux rate (gH+), and activities of ATP synthase and PM H+-ATPase significantly increased, and proton gradient (ΔpHpmf) between lumen and stroma decreased under Al stress. After removing apical buds of seedlings, the Y(I), Y(II), ETRI, ETRII, pmf, and gH+ under exogenous spraying IAA significantly increased, and ΔpHpmf significantly decreased in Mg addition than Al treatment alone, but they were no significant difference under none spraying IAA. The interaction of Mg and IAA directly increased quantum yields and electron transfer rates, and decreased O2– accumulation in Al-stressed seedlings with or without apical buds. These results suggest that IAA involves in Mg alleviation of Al-induced photosystem damage via increasing pmf and PM H+-ATPase activity, and decreasing ΔpHpmf.https://www.frontiersin.org/article/10.3389/fpls.2020.00746/fullaluminumcyclic electron flowIAAmagnesiumproton motive forceproton gradient |
| spellingShingle | Liantai Su Aimin Lv Wuwu Wen Peng Zhou Yuan An Yuan An Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress Frontiers in Plant Science aluminum cyclic electron flow IAA magnesium proton motive force proton gradient |
| title | Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress |
| title_full | Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress |
| title_fullStr | Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress |
| title_full_unstemmed | Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress |
| title_short | Auxin Is Involved in Magnesium-Mediated Photoprotection in Photosystems of Alfalfa Seedlings Under Aluminum Stress |
| title_sort | auxin is involved in magnesium mediated photoprotection in photosystems of alfalfa seedlings under aluminum stress |
| topic | aluminum cyclic electron flow IAA magnesium proton motive force proton gradient |
| url | https://www.frontiersin.org/article/10.3389/fpls.2020.00746/full |
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