Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes
Global climate change, specifically the intensification of marine heatwaves, affect seagrasses. In the Ria Formosa, saturating light intensities may aggravate heatwave effects on seagrasses, particularly during low spring tides. However, the photophysiological and antioxidant responses of seagrasses...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-06-01
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| Series: | Oceans |
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| Online Access: | https://www.mdpi.com/2673-1924/2/3/25 |
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| author | Monya M. Costa João Silva Isabel Barrote Rui Santos |
| author_facet | Monya M. Costa João Silva Isabel Barrote Rui Santos |
| author_sort | Monya M. Costa |
| collection | DOAJ |
| description | Global climate change, specifically the intensification of marine heatwaves, affect seagrasses. In the Ria Formosa, saturating light intensities may aggravate heatwave effects on seagrasses, particularly during low spring tides. However, the photophysiological and antioxidant responses of seagrasses to such extreme events are poorly known. Here, we evaluated the responses of <i>Cymodocea nodosa</i> exposed at 20 °C and 40 °C and 150 and 450 μmol quanta m<sup>−2</sup> s<sup>−1</sup>. After four-days, we analyzed (a) photosynthetic responses to irradiance, maximum photochemical efficiency (Fv/Fm), the effective quantum yield of photosystem II (ɸPSII); (b) soluble sugars and starch; (c) photosynthetic pigments; (d) antioxidant responses (ascorbate peroxidase, APX; oxygen radical absorbance capacity, ORAC, and antioxidant capacity, TEAC); (d) oxidative damage (malondialdehyde, MDA). After four days at 40 °C, <i>C. nodosa</i> showed relevant changes in photosynthetic pigments, independent of light intensity. Increased TEAC and APX indicated an “investment” in the control of reactive oxygen species levels. Dark respiration and starch concentration increased, but soluble sugar concentrations were not affected, suggesting higher CO<sub>2</sub> assimilation. Our results show that <i>C. nodosa</i> adjusts its photophysiological processes to successfully handle thermal stress, even under saturating light, and draws a promising perspective for <i>C. nodosa</i> resilience under climate change scenarios. |
| first_indexed | 2024-03-10T10:03:31Z |
| format | Article |
| id | doaj.art-5cc1a035eb434b089f1fad2c00fe1d5c |
| institution | Directory Open Access Journal |
| issn | 2673-1924 |
| language | English |
| last_indexed | 2024-03-10T10:03:31Z |
| publishDate | 2021-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Oceans |
| spelling | doaj.art-5cc1a035eb434b089f1fad2c00fe1d5c2023-11-22T01:41:59ZengMDPI AGOceans2673-19242021-06-012344846010.3390/oceans2030025Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light RegimesMonya M. Costa0João Silva1Isabel Barrote2Rui Santos3Centre of Marine Sciences (CCMAR), University of Algarve, Campus Gambelas, 8005-139 Faro, PortugalCentre of Marine Sciences (CCMAR), University of Algarve, Campus Gambelas, 8005-139 Faro, PortugalCentre of Marine Sciences (CCMAR), University of Algarve, Campus Gambelas, 8005-139 Faro, PortugalCentre of Marine Sciences (CCMAR), University of Algarve, Campus Gambelas, 8005-139 Faro, PortugalGlobal climate change, specifically the intensification of marine heatwaves, affect seagrasses. In the Ria Formosa, saturating light intensities may aggravate heatwave effects on seagrasses, particularly during low spring tides. However, the photophysiological and antioxidant responses of seagrasses to such extreme events are poorly known. Here, we evaluated the responses of <i>Cymodocea nodosa</i> exposed at 20 °C and 40 °C and 150 and 450 μmol quanta m<sup>−2</sup> s<sup>−1</sup>. After four-days, we analyzed (a) photosynthetic responses to irradiance, maximum photochemical efficiency (Fv/Fm), the effective quantum yield of photosystem II (ɸPSII); (b) soluble sugars and starch; (c) photosynthetic pigments; (d) antioxidant responses (ascorbate peroxidase, APX; oxygen radical absorbance capacity, ORAC, and antioxidant capacity, TEAC); (d) oxidative damage (malondialdehyde, MDA). After four days at 40 °C, <i>C. nodosa</i> showed relevant changes in photosynthetic pigments, independent of light intensity. Increased TEAC and APX indicated an “investment” in the control of reactive oxygen species levels. Dark respiration and starch concentration increased, but soluble sugar concentrations were not affected, suggesting higher CO<sub>2</sub> assimilation. Our results show that <i>C. nodosa</i> adjusts its photophysiological processes to successfully handle thermal stress, even under saturating light, and draws a promising perspective for <i>C. nodosa</i> resilience under climate change scenarios.https://www.mdpi.com/2673-1924/2/3/25seagrassesantioxidant responseheat haveshigh temperature<i>Cymodocea nodosa</i>oxidative stress |
| spellingShingle | Monya M. Costa João Silva Isabel Barrote Rui Santos Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes Oceans seagrasses antioxidant response heat haves high temperature <i>Cymodocea nodosa</i> oxidative stress |
| title | Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes |
| title_full | Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes |
| title_fullStr | Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes |
| title_full_unstemmed | Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes |
| title_short | Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass <i>Cymodocea nodosa</i> under Contrasting Light Regimes |
| title_sort | heatwave effects on the photosynthesis and antioxidant activity of the seagrass i cymodocea nodosa i under contrasting light regimes |
| topic | seagrasses antioxidant response heat haves high temperature <i>Cymodocea nodosa</i> oxidative stress |
| url | https://www.mdpi.com/2673-1924/2/3/25 |
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