Physiological Effect of Potato Genotypes and Salicylic Acid on Plantlets Growth and Microtuber Production under Salt Stress

This study was conducted to investigate the effectiveness of SA (10 and 100 μmol) for induction of salinity tolerance of two potato genotypes “Proventa” and line “97-980” during vegetative and micro-tuberization stages. Results showed that decreasing of plantlet weight and length as well as microtuber weight under saline conditions differed according to genotypes and SA concentration. Although line “97-980” had low percentage of decreasing in weight and length of plantlets compared to “Proventa” under saline condition, Proventa cv. Gave high microtubers weight. Line 97-980 recorded high reducing sugars, phenolics, proline, amino acids and proteins as well as high activity of peroxidase (POD). On contrary, “Proventa” had high concentration of total chlorophylls and high activity of superoxide dismutase(SOD) and catalase (CAT).The decrease in plantlets growth was lower in line 97-980 compared to” Proventa” under low concentration of SA. Microtubers weight in “Proventa” was higher with addition of 10 μmol through increment in most investigated biochemical compounds and high antioxidants enzymes activity. It may be concluded that high content of reducing sugars, phenolics, proline, amino acids, proteins as well as high activity of POD could work as selectable markers for in vitro potato tolerance to salinity. Addition of low concentration of SA had beneficial effect on physiological