Pavlović, Iva; Pěnčík, Aleš; Novák, Ondřej; Vujčić, Valerija; Radić Brkanac, Sandra; Lepeduš, Hrvoje; Strnad, Miroslav; Salopek-Sondi, Branka (2018) Short-term salt stress in Brassica rapa seedlings causes alterations in auxin metabolism. Plant physiology and biochemistry, 125 . pp. 74-84. ISSN 0981-9428
Abstract
Salinity is one of major abiotic stresses affecting Brassica crop production. Here we present investigations into the physiological, biochemical, and hormonal components of the short-term salinity stress response in Chinese cabbage seedlings, with particular emphasis on the biosynthesis and metabolism of auxin indole-3-acetic acid (IAA). Upon salinity treatments (50- 200 mM NaCl) IAA level was elevated in a dose dependent manner reaching 1.3-fold increase at the most severe salt treatment in comparison to the control. IAA precursor profiling suggested that salinity activated the indole-3-acetamide and indole-3-acetaldoxime biosynthetic pathways while suppressing the indole-3-pyruvic acid pathway. Levels of the IAA catabolites 2-oxoindole-3-acetic acid and indole-3-acetic acid-aspartate increased 1.7- and 2.0-fold, respectively, under the most severe treatment, in parallel with those of IAA. Conversely, levels of the ester conjugate indole-3-acetyl-1-O-ß-d-glucose and its catabolite 2-oxoindole-3-acetyl-1-O-ß-d-glucose decreased 2.5- and 7.0-fold, respectively. The concentrations of stress hormones including jasmonic acid and jasmonoyl-isoleucine (JA and JA-Ile), salicylic acid (SA) and abscisic acid (ABA) confirmed the stress induced by salt treatment: levels of JA and JA-Ile increased strongly under the mildest treatment, ABA only increased under the most severe treatment, and SA levels decreased dose-dependently. These hormonal changes were related to the observed changes in biochemical stress markers upon salt treatments: reductions in seedling fresh weight and root growth, decreased photosynthesis rate, increased levels of reactive oxygen species, and elevated proline content and the Na+/K+ ratio. Correlations among auxin profile and biochemical stress markers were discussed based on Pearson’s coefficients and principal component analysis (PCA).
Item Type: | Article | ||||||||
---|---|---|---|---|---|---|---|---|---|
Uncontrolled Keywords: | auxin metabolism ; Brassica rapa ssp. pekinensis ; growth inhibition ; reactive oxygen species ; short-term salinity stress ; stress hormones ; principal component analysis | ||||||||
Subjects: | NATURAL SCIENCES NATURAL SCIENCES > Biology NATURAL SCIENCES > Biology > Botany |
||||||||
Divisions: | Division of Molecular Biology | ||||||||
Projects: |
|
||||||||
Depositing User: | Branka Salopek Sondi | ||||||||
Date Deposited: | 19 Nov 2019 10:39 | ||||||||
URI: | http://fulir.irb.hr/id/eprint/4613 | ||||||||
DOI: | 10.1016/j.plaphy.2018.01.026 |
Actions (login required)
View Item |