Effect of Humic Acid and Seaweed Extract on Growth and Yield of Quinoa under Drought Stress

This study attempts to investigate the effect of application of humic acid and seaweed extract on morphology, growth, yield, and yield components of quinoa under drought stress in 2018-2019 in two different locations, Qasr Shirin and Dalahou. It has been performed as split plots in a randomized complete block design with 4 replications. Experimental treatments include three irrigation treatments (full irrigation, irrigation cut-off at the beginning of flowering and irrigation cut-off at the beginning of seed filling) and foliar spraying treatments with different amounts of humic acid (foliar application at the rate of 1.5 kg / ha and 2 Kg / ha) and seaweed extract (foliar application at 1 kg / ha and 1.5 kg / ha) along with a control treatment. Results show that seed yield in Dalahou region under normal condation has been 24.78% higher than Qasrshirin region. Seed yield in different irrigation treatments under the influence of foliar application show that in all irrigation treatments, the effect of foliar application of humic acid and seaweed extract on seed yield has been positive compared to the control. In full irrigation conditions, the highest seed yield is obtained from foliar application of humic acid, while in irrigation cut-off treatments, the effect of seaweed extract on seed yield has been better than humic acid. The weight of 1000 seeds in quinoa produced in Dalahu region has been more than Qasrshirin region but in both regions drought stress has reduced the 1000 seeds weight. In all irrigation treatments, application of humic acid and algae extract has increased 1000-seed weight.