The effect of irrigation- cut off on chlorophyll content and yield of cotton genotypes (Gossypiumhirsutum L.)

In order to evaluate the effect of cut-irrigation on chlorophyll content and yield of different genotypes of cotton, a field experiment were performed in Haji Abad (28°36'N, 54°41'E) during 2014-2015 growing season. The experiment was conducted in split plot design with three replications. The main plot was drought levels (Full irrigation (every 10 days) and irrigation-cut for two periods (30 days)) and the sub-plot was different cotton genotypes (Super Elit Arian, Super ElitGolestan, Kiza, SB-35, Opal, Super ElitBakhtegan, T-2, Dr-Omoomi, Khandagh, Superokra, Termez-14, T-3, Sahel, Sepid, Silend, Armaghan, Pak, Oltan(. Irrigation cutting reduced the chlorophyll content of different cotton genotypes. The highest and lowest β-carotene, Xanthophyl, chlorophyll a, chlorophyll b and total chlorophyll were obtained for Termez-14 and Dr-Omoomi genotypes, respectively. Under irrigation cutoff some genotypes had higher levels of chlorophyll content and yield such as, Khandagh, Pak, Opal, Armaghan, Sahel and Oltan which shows that these genotypes can better tolerate drought stress condition.