Improving drought tolerance of quinoa plant by foliar treatment of trehalose

Abstract

Two field experiments were conducted during two successive seasons (2014/2015 and 2015/2016) at the Experimental Station of National Research Centre, Nubaria district, Beheira Governorate, Egypt, to study the effect of foliar treatment of quinoa plants with trehalose (Tre) (100µM and 500µM) on growth, photosynthetic pigments, seed yield quantity & quality, in fever of nutritional and antioxidant compounds in the yielded quinoa seeds which subjected to water deficiency (skipping two irrigation times at 50 & 60 days after sowing). Water deficiency caused marked decreases in quinoa plant growth parameters (shoot height, fresh and dry weights of shoot/plant) and photosynthetic pigments with marked increases in root growth parameters (root length, fresh and dry weight of root/plant). Drought stress decreased yield and yield attributes, carbohydrates, protein, nitrogen, phosphorous and potassium contents.  Meanwhile oil percentage, phenolic and flavonoids contents increased by drought stress. Antioxidant activity at 50 and 100µg/l showed significant increases in response to drought stress. On the other hand, Tre treatments proved to be effective in enhancing growth parameters and photosynthetic pigments of drought stressed plants. Trehalose treatments at different levels caused marked increases in yield and yield attributes, carbohydrate, protein, oil, nitrogen, phosphorous, potassium, total phenolic, flavonoids contents, and antioxidant activity of the yielded seeds either in non stressed or drought stressed plants relative to corresponding controls. Generally, 500 µM Tre was the most pronounced and effective treatment in alleviating the deleterious effect of drought stress on quinoa plants.