Total soluble proteins were extracted from commercial Egyptian cotton Gossypium barbadense, that are genetically characterized as salt tolerance varieties, e.g. Giza 45, Giza 75 and as salt sensitive varieties, e.g. Giza 80, and Dendera. Total soluble proteins examination on One-Dimensional SDS-PAGE showed that the control salt treatments protein pattern are still present in the salt treated samples. However, proteins that are induced in response to salt treatments are present in greater abundance at molecular weights (14 KD, and 25 KD). Comparing protein patterns induced in Giza 45, Giza 75, Giza 80 and Dendera after salt treatments (2000 ppm, 4000 ppm, and 8000 ppm) showed differences of polypeptide profile and presence of proteins in molecular weight regions (14 KD, 25 KD, 45 KD and 90 KD). The protein pattern synthesized in-vivo for Giza 45 and Giza 80 using no salt treatments showed similar pattern to the salt-induced treatments. Some differences were shown in higher salt concentrations at molecular weight (25 KD, 45 KD, and 90KD). In vivo-labelling protein experiments for seedling tissue indicated the presence of appreciable amounts of protein in the control lanes of Giza 45. The authors observed increasing level of induced proteins synthesized by Giza 45 and Giza 80, as salt concentration increased. Polymerase chain reaction (PCR) analysis was undertaken for the previous Egyptian cotton varieties genomic DNA using oligonucleotide primers combinations designed from gene bank data base screening of salt-induced genes. PCR analysis indicated the presence of some salt-induced

genes in agreement with the In-vivo labelling protein analysis information. This data suggests that proteins which accumulate in cotton leaf and seedling tissue in response to elevated salt concentration are inducible salt tolerance proteins, and can accumulate to substantial levels in field plants. In G. barbadense Var. Giza 45, and Var. Giza 80 protein levels synthesized in-vivo at different salt concentration showed differences at high concentrations, due to the presence of salt-tolerant induced proteins.