This investigation was conducted over two consecutive seasons (2021 and 2022) for testing ortho salicylic acid influence on sweet potato plants (Ipomoea batatas L.) under the water deficiency effect. It was aimed to reinforce sweet potato plants growth process and yield parameters by using different concentrations of ortho salicylic acid (4, 6 and 8%) as well as the control under different levels of water supply (100, 75 and 50% of ETc i.e. evapotranspiration) in sandy loam soil conditions at Belbeis region – El Sharkia Governorate, Egypt.

The data obtained during the two experimental seasons clearly disclosed that, all the applied treatments enhanced both plants growth process and yield parameters as compared to the control. In particular, spraying with ortho salicylic acid (6 and 8 %) in combination with water supply (100 or 75 of ETc) enhanced vegetative growth and increased the tuber yield and quality as compared to the control, but the most effective treatment for water productivity was gained by ortho salicylic acid 8 % combination with water supply ETc 75 %, which produced 6.77 and 8.09 kg m-3 in the first and the second seasons, respectively.