Effect of exogenous gibberellic acid on germination, seedling growth and phosphatase activities in Lettuce under salt stress

The effect of gibberellic acid on germination and seedling growth of lettuce variety, Vista, under salinity conditions was studied. A reduction in germination percentage, roots and shoots length and fresh weight were observed under salt stress. At the same time, acid phosphatase and phytase activities in roots were reduced by NaCl. The exogenous application of gibberellin increased germination percentage and improved length and fresh weight of roots and shoots under salt treatment. It also increased both acid phosphatase and phytase activities in roots under this constraint. The application of gibberellic acid compensated for the negative effect of salinity.Keywords: Acid phosphatase, germination, gibberellic acid, lettuce, phytase, salinity, seedling growt

Effect of salinity on Arabidopsis thaliana seed germination and acid phosphatase activity

The salt tolerance of four accessions of Arabidopsis thaliana (COL (Columbia), NOK2, N1438 and N1380) was evaluated during germination by the capacity of seeds to germinate in the presence of 50 mM NaCl and to maintain adequate acid phosphatase activity. Our results show that saline conditions reduced the final germination percentage, speed of germination and delayed the germination processes of accessions NOK2, N1438 and N1380. In contrast, 100% of germination was found in COL under salt-stress conditions. In the presence of NaCl 50 mM, acid phosphatase activity increased in the first 24 h, the activity reaching the control level in germinating seeds of COL, but in the three other accessions NOK2, N1438 and N1380, acid phosphatase activity diminished under salt stress. These findings suggest that changes in the phosphatase enzymes might play an important role in the acclimation of COL seeds to the changing environmental conditions