Effect of ash carbon nanofibers on GABA shunt pathway in germinating seeds of tomato (Lycopersicon esculentum Mill., c.v. Rohaba.) under salt stress

Abstract

The aim of the current study was to examine the effect of black ash carbon nanofibers (CNFs) on gamma-aminobutyric acid(GABA) shunt pathway in germinating seeds of tomato (Lycopersicon esculentum Mill., c.v. Rohaba) under salt stress. Seed’s germinationpattern, seed moisture content, GABA shunt metabolite levels (GABA, Glutamate and Alanine), total proteins and total carbohydrates,and the level of oxidative damage in response to sodium chloride (NaCl) treatments were determined. A significant increase of moisturecontent in CNFs treated seeds associated with significant increases in germination percentage was found. Data also showed a significantincrease in GABA shunt metabolites in treating seeds compared to control seeds under different concentrations of NaCl. The totalprotein and carbohydrate levels significantly increased with positive correlation in control and treated seeds as NaCl concentrationincreased. A significant increase in MDA level was found in both treated and control seeds under salt stress. However, treated seedsshowed lower MDA accumulation compared to control seeds. Our results suggested that the elevation of GABA in CNFs treated seedswas to maintain metabolic stability under salt stress, while, in control seeds, GABA elevation was to mitigate the effect of salt stress.CNFs activated GABA shunt, which might be involved in reduction of MDA accumulation and alleviation of oxidative damage undersalt stress. In conclusion, CNFs enhanced tomato seed germination during salt stress.