Genetic and molecular evaluation of silica nanoparticles effects on tomato performance under seawater stress and their influence on the expression of two salinity tolerance related genes

Two different silica nanoparticles (SiNPs) from different sources; chemical and biogenic were used with different doses (50 mg/l and 100 mg/l) for each in an attempt to evaluate their effects on three tomato varieties having different levels of salt stress tolerance (Edkawy, Rio Grande and Super Strain B). Tomato seeds were germinated on half MS media containing different combinations of seawater dilutions and SiNPs. Seed germination, seedling growth and vegetative growth of tomato plants were significantly increased after exposure to SiNPs under salinity stress. SDS-PAGE was carried out for the adult plants to identify protein banding variations. Protein profile analysis showed differences in at least four bands with molecular weights of 90, 70, 60 and 40 KDa which could be used as positive markers that help in the evaluation of salinity tolerance genotypes and also for determining the useful doses of SiNPs required for salinity tolerance enhancement, Quantitative real time PCR (qPCR) was applied for measuring the effects of silica nanoparticles on the gene expression of two distinguished salinity tolerance genes (APX2 and AREB). Exogenous SiNPs could enhance the gene expression patterns of APX2 and AREB genes. Eventually, the addition of SiNPs treatment in seedling stage was sufficient to affect positively tomato plant adaptation under salinity stress, Biogcnic RHSiNPs at 100 mg /I proved to he the best treatment against the highest concentration of salinity therefore, it could be recommended for a potential association with tomato plant salinity tolerance.