Study on some biochemical characteristics of cotton genotypes under irrigation by saline water

This experiment was laid out in order to study on effect of irrigation saline water on biochemical characteristics of mutant cotton lines in Isfahan Agricultural and Natural Resources Center, Iran at 2014-2015, by using of split plot arrangement based on complete block design with three replications. Experimental treatments were three irrigation water [4 (as control), 8 and 12 dS m-1] at main plots and three cotton genotypes (LM1673, LM1303 and Shayan) in sub plots. Results showed that the effect of irrigation using saline water on all traits was significant except reducing and non-reducing sugars. Effect of cultivar was significant on starch content and interaction between irrigation using saline water and cultivars was significant on soluble and non-reducing sugars, starch content and carotenoids. Irrigation by 12 dS m-1 saline water, soluble protein and soluble sugars increased as 50% and prolin content increased as 45% rather than control treatment. Proxidase (POX) enzyme activity in irrigation by 8 dS m-1 saline water treatment increased as 50% rather than irrigation by 12 dS m-1 saline water treatment. By increasing of irrigation water salinity, decreased chlorophyll content (40% rather than 8 dS m-1 saline water) and increased relief pigments such as carotenoids (50%) and anthocyanin (23%). In many traits, because of non-significant different amomg genotypes and with regards to high tolerance characteristics of Shayan genotype to salinity can be concluded that LM-1303 and LM-1673 had high tolerance to salinity same to Shayan genotype. With regard to higher soluble sugar, non-reducing sugar and carotenoids in LM-1303 genotype, can be concluded that this genotype had better physiological status under salinity compare to Shayan genotype.