I agree with Svetoslav Anev.

Thanks Svetoslav Anev, but my query is on all the plant genome posses almost same genes that are mainly able to tolerate against salinity, but some plants can tolerate salt while others can't survive, Why? It is only due to expression pattern of those genes, or other mechanism involved. 

Dear Borhan,

partially you've answered your own question. As there is some difference between glycophytes and halophytes It means that their genotypesae not same You'll see in above offered articles that the mechanisms of salt adaptation are different and not all plants possess them. There exist genes which are responsible for these mechanisms.

regards 

Almost is a misleading way of comparison. Compatible solute capability as well root active flux and by-pass flow are specific traits related fo very few genes. Some are regulated during development and thus expression profile differs but during a specific phase. http://onlinelibrary.wiley.com/doi/10.1046/j.1365-3040.1999.00418.x/pdf.

I feel , its the difference of distribution of vacuoles within  the cells of halophytes against glycophytes, besides having some indigenous property of salt exclusion property..

Hello Borhan,

You are right. There is high similarity between genome of glycophytes and halophytes. You may know that there is more than 90% similarity between Arabidopsis and Thellungiella genome. The difference is that their regulation under stress conditions. The halophytes have high copy numbers of salt tolerance related genes or high transcript level under control condition (May be there is difference in promoter region). This keeps halophytes well prepared for stress condition.Please read a review written by Bose et al. 2014 (https://academic.oup.com/jxb/article/65/5/1241/2884858/ROS-homeostasis-in-halophytes-in-the-context-of). Recently, there is very good research article entitled, "A Single Amino Acid Substitution in the Sodium Transporter HKT1 Associated with Plant Salt Tolerance" This article indicated that there are some minor differences in gene sequence of halophytes as compared to glycophytes which are responsible for their high salt tolerance.

I hope, I have answered your query.

Best luck.

Ganesh

Post translational modifications such as phosphorylation of some proteins involved in salt stress tolerance  can contribute substantially to differences in tolerance between halophytes and glycophytes. In such cases, whereas there is activation of the protein in halophytes, it remains inactive in glycophytes. See more details in Himabindu et al 2016  Environmental and experimental Botany vol 124.