Characterization of the Sos1, Serk1, and Wee1 Conferring a Defense Response to Salt Stress in Alfalfa (Medicago Sativa L.) Callus

Abstract

Alfalfa, which is one of the most important forages, suffers from salt stress that dips its productivity. In the current survey, some biochemical parameters such as proline, soluble sugar, Na+, K+ contents, and the expressions levels of SOS1, SERK1, and WEE1 genes were studied in the NaCl stress response of callus cells belonging to the various alfalfa genotypes (omer Bey, Elci, and Mus). The callus developed from leaf explants was grown onto the co-culture medium containing MS basal and different NaCl levels (50, 80, and 110 mM) for 3, 6, and 9 months in a growth chamber at 28 degrees C and 16/8 h photoperiod conditions. In sum, the important characteristics of callus were determined among the genotypes in terms of NaCl resistance. Overall, proline content peaked at 110 mM NaCl, as well as, the greatest and lowest proline amounts were observed in the omer Bey genotype within a period time of 9 months. Additionally, it showed an upward trend in resistance to the soaring NaCl concentration. Although, compared to the controls, the content the soluble sugar of each genotype moved upward at the salt applications and throughout the experimental periods (3, 6, and 9 months). According to the data, not only, the K+/Na+ ratio uplifted in parallel with a rise in salt concentrations in all genotypes but also in omer bey genotype, especially at high salt 80 and 110 mM NaCl doses, a downward tendency was observed. The provided presentation of gene expression analysis outlined the data on expresses of SOS1, SERK1, and WEE1 genes were a ceiling trend under 50 mM NaCl in the three genotypes and a descending trend at 80 and 110 mM NaCl compared to their controls. In conclusion, the data suggest that the expression levels of these genes are effective in promoting the alfalfa callus cells in response to salt stress induced by NaCl.