TY - JOUR
T1 - Melatonin positively influences the photosynthetic machinery and antioxidant system of avena sativa during salinity stress
AU - Varghese, Nisha
AU - Alyammahi, Onoud
AU - Nasreddine, Sarah
AU - Alhassani, Abla
AU - Gururani, Mayank Anand
N1 - Funding Information:
Funding: This research was funded by UAE University, Centre based grant [31R110] and SURE plus grant (G00003057). The APC was funded by [31R110].
Funding Information:
This research was funded by UAE University, Centre based grant [31R110] and SURE plus grant (G00003057). The APC was funded by [31R110]. Acknowledgments: The authors would like to acknowledge the UAE University and Khalifa Centre for Genetic Engineering and Biotechnology (KCGEB) for their financial support and research facilities.
Funding Information:
Acknowledgments: The authors would like to acknowledge the UAE University and Khalifa Centre for Genetic Engineering and Biotechnology (KCGEB) for their financial support and research facilities.
Publisher Copyright:
© 2019 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2019/12
Y1 - 2019/12
N2 - Recent studies have demonstrated melatonin protects various crops against abiotic stresses. However, the effects of melatonin on the photosynthetic apparatus of stressed plants is poorly characterized. We investigated the effects of melatonin pretreatment on photosynthesis and tolerance to salinity stress in Avena sativa (oat) plants. Oat plants were exposed to four treatments (three replicate pots per treatment): well-watered (WW; control); watered with 300 mM salt solution for 10 days (NaCl); pretreated with 100 µM melatonin solution for 7 days then watered normally for 10 days (Mel+W); or pretreated with 100 µM melatonin for 7 days then 300 mM salt for 10 days (Mel+NaCl). Considerable differences in growth parameters, chlorophyll content, stomatal conductance, proline accumulation, lipid peroxidation, electrolyte leakage, and growth parameters were observed between groups. Genes encoding three major antioxidant enzymes were upregulated in the Mel+NaCl group compared to the other groups. Chlorophyll-a fluorescence kinetic analyses revealed that almost all photosynthetic parameters were improved in Mel+NaCl plants compared to the other treatments. Analysis of genes encoding the major extrinsic proteins of photosystem II (PSII) revealed that PsbA, PsbB, PsbC, and PsbD (but not PsbO) were highly upregulated in Mel+NaCl plants compared to the other groups, indicating melatonin positively influenced photosynthesis under control conditions and salt stress. In addition, melatonin upregulated stress-responsive NAC transcription factor genes in plants exposed to salt stress. These findings suggest melatonin pretreatment improves photosynthesis and enhances salt tolerance in oat plants.
AB - Recent studies have demonstrated melatonin protects various crops against abiotic stresses. However, the effects of melatonin on the photosynthetic apparatus of stressed plants is poorly characterized. We investigated the effects of melatonin pretreatment on photosynthesis and tolerance to salinity stress in Avena sativa (oat) plants. Oat plants were exposed to four treatments (three replicate pots per treatment): well-watered (WW; control); watered with 300 mM salt solution for 10 days (NaCl); pretreated with 100 µM melatonin solution for 7 days then watered normally for 10 days (Mel+W); or pretreated with 100 µM melatonin for 7 days then 300 mM salt for 10 days (Mel+NaCl). Considerable differences in growth parameters, chlorophyll content, stomatal conductance, proline accumulation, lipid peroxidation, electrolyte leakage, and growth parameters were observed between groups. Genes encoding three major antioxidant enzymes were upregulated in the Mel+NaCl group compared to the other groups. Chlorophyll-a fluorescence kinetic analyses revealed that almost all photosynthetic parameters were improved in Mel+NaCl plants compared to the other treatments. Analysis of genes encoding the major extrinsic proteins of photosystem II (PSII) revealed that PsbA, PsbB, PsbC, and PsbD (but not PsbO) were highly upregulated in Mel+NaCl plants compared to the other groups, indicating melatonin positively influenced photosynthesis under control conditions and salt stress. In addition, melatonin upregulated stress-responsive NAC transcription factor genes in plants exposed to salt stress. These findings suggest melatonin pretreatment improves photosynthesis and enhances salt tolerance in oat plants.
KW - Abiotic stress
KW - Chlorophyll-a
KW - Fluorescence
KW - Melatonin
KW - Photosystem II
KW - Quantitative PCR
KW - Reactive oxygen species
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U2 - 10.3390/plants8120610
DO - 10.3390/plants8120610
M3 - Article
AN - SCOPUS:85076899911
SN - 2223-7747
VL - 8
JO - Plants
JF - Plants
IS - 12
M1 - 610
ER -