The γ-Aminobutyric Acid (GABA) Alleviates Salt Stress Damage during Seeds Germination of White Clover Associated with Naâº/K⺠Transportation, Dehydrins Accumulation, and Stress-Related Genes Expression in White Clover.
Int J Mol Sci
; 19(9)2018 Aug 25.
Article
en En
| MEDLINE
| ID: mdl-30149642
ABSTRACT
The objective of this study was to determine the effect of soaking with γ-aminobutyric acid (GABA) on white clover (Trifolium repens cv. Haifa) seed germination under salt stress induced by 100 mM NaCl. Seeds soaking with GABA (1 µM) significantly alleviated salt-induced decreases in endogenous GABA content, germination percentage, germination vigor, germination index, shoot and root length, fresh and dry weight, and root activity of seedling during seven days of germination. Exogenous application of GABA accelerated starch catabolism via the activation of amylase and also significantly reduced water-soluble carbohydrate, free amino acid, and free proline content in seedlings under salt stress. In addition, improved antioxidant enzyme activities (SOD, GPOX, CAT, APX, DHAR, GR and MDHR) and gene transcript levels (Cu/ZnSOD, FeSOD, MnSOD, CAT, GPOX, APX, MDHR, GPX and GST) was induced by seeds soaking with GABA, followed by decreases in O2â-, H2O2, and MDA accumulation during germination under salt stress. Seeds soaking with GABA could also significantly improve Naâº/K⺠content and transcript levels of genes encoding Naâº/K⺠transportation (HKT1, HKT8, HAL2, Hâº-ATPase and SOS1) in seedlings of white clover. Moreover, exogenous GABA significantly induced the accumulation of dehydrins and expression of genes encoding dehydrins (SK2, Y2K, Y2SK, and dehydrin b) in seedlings under salt stress. These results indicate that GABA mitigates the salt damage during seeds germination through enhancing starch catabolism and the utilization of sugar and amino acids for the maintenance of growth, improving the antioxidant defense for the alleviation of oxidative damage, increasing Naâº/K⺠transportation for the osmotic adjustment, and promoting dehydrins accumulation for antioxidant and osmotic adjustment under salt stress.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Estrés Fisiológico
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Germinación
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Trifolium
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Plantones
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Tolerancia a la Sal
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Ácido gamma-Aminobutírico
Tipo de estudio:
Risk_factors_studies
Idioma:
En
Revista:
Int J Mol Sci
Año:
2018
Tipo del documento:
Article
País de afiliación:
China
Pais de publicación:
CH
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SUIZA
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SUÍÇA
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SWITZERLAND