Effect of foliar spray of calcium lactate on the growth, yield and biochemical attribute of lettuce (Lactuca sativa L.) under water deficit stress

Abstract

The field experiment was conducted to evaluate the effect of foliar spray of calcium lactate (Ca) on fresh yield and biochemical attribute of lettuce (Lactuca sativa L.) under water deficit stress, in a split plot form based on a randomized complete block design with three Irrigation regimes (70, 85 and 100% ETc) and three calcium lactate treatment levels (0, 0.75 and 1.5 g L^-1) in three replicates. Results revealed that water deficit stress significantly reduced the growth and yield of plant, leaf relative water contents, excised leaf water retention and N, P and Mg absorption while led to increase anthocyanin, phenol and flavonoids contents, antioxidant activity, peroxidase and catalase activity and water use efficiency. The results of our research indicated that the application of CaL 1.5 g L^-1 is capable of increasing lettuce yield, under field conditions with 30% less than optimal irrigation. CaL treatment showed a clearly protective effect in stressed plants, enhancing their leaf water status, antioxidant capacity and N and Ca contents in comparison to untreated plants. Therefore, feeding leaves by CaL with increasing antioxidant activity and nutrients content especially N led to increase growth and fresh yield of lettuce under normal irrigation and water deficit conditions.