Effect of Water Deficit Stress at Vegetative and Reproductive Stages on Some Physiological and Biochemical Characteristics of Sage (Salvia officinalis L.)

In order to study the effect of water deficit stress at vegetative and reproductive stages on activity of some antioxidant enzymes, accumulation of compatible osmolytes, relative water content and yield in sage (Salvia officinalis L.), a field experiment was conducted a randomized complete block design with three replications at the Experimental Field of the Hamedan Agriculture and Natural Resources Research and Education Center during 2020. Treatments were irrigation levels based on maximum allowable depletion of available soil water and their combination that considered for both vegetative and reproductive stages, so that 35% maximum water depletion as the control and 60% and 85% as water deficit stress levels were applied as moderate and severe stress, respectively during the plant growth. Also, 60% and 85% at vegetative stage, 60% and 85% at reproductive stage as well as vegetative and reproductive control were considered. The results showed that, the highest superoxide dismutase activity belonged to moderate and severe stress at complete and vegetative growth stages. The highest catalase activity were obtained from moderate and severe stress at reproductive stage and highest peroxidase activity from severe stress at vegetative and reproductive growth stages. Leaf relative water content was reduced under water deficit stress, while the amount of prolineand electrolyte leachage percentage were increased. Control treatment showed the highest biological yield (14700 kg.ha^-1). Also the highest amount of protein was obtained from the control, moderate stress at the complete and vegetative and reproductive growth stages. The greatest percentage of soluble carbohydratewere belonged to moderate stress at the complete and reproductive growth stage.