Some Eco-physiological and Agronomic Responses of Several Salinity Tolerant Safflower Varieties to Water Deficit Stress

The goals of study were to recognize the effects of water deficit on eco-physiological and agronomic responses of safflower and introducing drought tolerant genotypes to cultivate in saline and dry lands.

The experiment was conducted as split plot based on randomized complete blocks design with three replications in the East Azarbaijan Agriculture and Natural Resources Research and Education Center during two cropping seasons (2017-19). The experimental factors included drought stress as non-stressed and stressed from flowering to maturity and six safflower genotypes including Padideh, Golemehr, Mexico14, Mexico248, Mexico295 and Parnian.

Seed and oil yields and yield components of genotypes decreased by drought. Water deficit stress decreased RWC, stomatal conductance and leaf chlorophyll index significantly. Amounts of these characters were significantly different among genotypes. Correlations among studied traits were significant. Stomatal conductance and RWC indicated significant correlations with capitulum number per plant and oil percent. Also RWC indicated significant correlation with seed yield. Correlations among capitulum number per plant and grain number per capitulum with each other and seed oil percent, seed and oil yields, were positive and significant. These yield components had important role in productivity.

stomatal conductance and RWC are able to reflect the effects of late season drought stress on safflower and can be used to select drought-tolerant genotypes. Golemehr, Mexico14, Mexico248 and Mexico295 genotypes indicated higher seed and oil yields in both normal and drought conditions and were seen suitable to cultivate in saline areas around Ormieh lake and areas with similar climate.