Abstract
The present study was conducted to evaluate the effect of salinity stress on growth of Cassia italica and role of gamma. amminobutyric acid (GABA) in mitigating the salt stress induced damaging effects. Antioxidant activity, level of endogenous growth hormones and other biochemical parameters were evaluated. Salt stress enhanced the production of reactive oxygen species (ROS) resulting in the enhanced lipid peroxidation which was however reduced by application of GABA. Increased lipid peroxidation in salt stressed plants caused an obvious, reduction in the total lipid content as compared to GABA treated plants. The antioxidant enzymes were higher in GABA treated plants which indicated a reduction of oxidative, damage.
The concentrations of growth hormones like indole acetic acid (IAA), indole butyric acid (IBA), gibberellic acid-1 (GA(1)), and gibberellic acid-4 (GA(4)) were reduced by salt stress, while enhanced by GABA treatment. In addition GABA treated plants maintained lower levels of sodium and chloride ions as compared to salt stressed plants. It could be concluded that toxic effects of salt stress on growth, antioxidant system, hormones and mineral nutrients in Cassia italica could be alleviated by exogenous application of GABA.