Differential response of some potato varieties grown under drought conditions

Abstract: The current investigation was conducted to test the response of five potato varieties; i.e. , Arizona, Diamant, Markies, Spunta and Valor, to different irrigation levels during the summer seasons of 2018 and 2019 under Egyptian conditions. The irrigation levels were 100, 75 and 50% of evapotranspiration (ET). Different traits of vegetative growth, some chemical characters and yield were increased with increasing irrigation levels from 50 to 100% of ET for all tested varieties. While there were increased bound water and proline content in leaves as well as dry matter and starch content percentages in tubers under drought conditions. Concerning potato varieties, Diamant in both growing seasons gave the highest values for most growth measurements, tuber yield and its components as well as, some parameters of growth analysis, physical and chemical characters and water use efficiency (WUE), followed by the Arizona variety. In terms of the interaction between potato varieties and irrigation levels, Diamant and Arizona cv. were the most drought-tolerant cultivars, with 75 and 50 % ET, respectively, whereas Spunta cv. was the most sensitive. Furthermore, bound water and proline content in leaves, as well as the dry matter and starch content percentage in tubers, increased with decreasing irrigation levels.