P0798 Genes Expression Profiles Related to Ion Homeostasis in Wheat (Triticum aestivum) Seeds and Seedlings Under Saline Conditions

Somayeh yousefnejad Kivi , wageningen university, wageningen, Netherlands
Wilco Ligterink , wageningen university, wageningen, Netherlands
Salinity is one of the most important abiotic stresses that have an effect on the growth, development and yield of plants. Plants have different mechanisms to avoid or reduce harmful effects of salt stress. One of the most important mechanisms of tolerance to salt stress involve Na+ exclusion from transpiration stream and sequestration of Na+ and Cl- in vacuoles, thereby protecting cytoplasmic processes from ion toxicity. K+/Na+ selectivity is one of the most important traits that have a high correlation with yield and biomass in response to salt stress. Under Na+ stress activity of the K+ transporters result in higher discrimination of K+/Na+ for reducing influx of Na+. In this study four wheat cultivars, two salt-sensitive and two salt-resistant were selected based on different physiological traits. Seeds and seedlings of these four cultivars were treated with 150mM NaCl and we evaluated expression levels of candidate genes that are involved in maintaining K+/Na+ homeostasis in higher plants, including: HKT1, HKT2, HKT8, SOS1 SOS2, SOS3, NHX1,NHX2, HAK1, LCT1, HA1and AVP1 in coleoptiles and radicles of the seedlings. We observed different expression levels of those genes in salt-sensitive and tolerant cultivars. On the basis of the different expression levels of those genes, we hypothesis that the ion compartmentation in organelles is different in salt-tolerant compared to the salt-sensitive plants and we plan to measure K+ and Na+ concentrations in different sub-cellular organelles.