GENETIC AND PHYSIOLOGICAL ANALYSIS OF COTTON CULTIVARS UNDER SALT STRESS

The salinity caused changes in plant metabolic processes. Cotton is one of the important fiber products which may be affected by salinity stress in Iran. In the present study, the effects of salinity stress and salicylic acid (SA) as improvement of abiotic stress were examined on biochemical traits and retrotransposon based markers profile (TRAP and REMAP) in cotton cultivars. Cotton seeds of two cultivars (GT40 and NNC) were cultivated in pots and different treatments; control plants with normal irrigation, 0.5 and 1mM SA, 100 and 150mM NaCl treatments and, combination of 0.5mM SA and 150mM NaCl were performed. Physiological, morphological, cellular and, genetic diversity parameters were measured after treating and following seven days of irrigation. Activity of antioxidant enzymes; catalase, peroxidase and proline in 150mM NaCl treated plants were more than other treatments. In comparison to two cultivars, GT40 cultivar had a higher activity of antioxidant enzymes. Based on retrotransposon based markers analyses, the highest heterozygosity was shown in 0.5mM SA treatment of GT40 cultivar as well as 0.5 mM SA, 150mM NaCl treatments in NNC cultivar. Totally, GT40 showed the highest genetic variation in retrotransposon profiles. The Salt stress and salicylic acid treatment provided discriminate profiles from retrotransposon movement.