Determination of Crop Coefficients and Water Requirements of Cucumber (Cucumis Sativus) Under Greenhouse Conditions

This study investigated the growth-stage-specific crop coefficient (Kc) and consumptive use (CU) of Cucumber plant in the rainforest ecological zone of Ibadan Nigeria. Daily CU and Kc for Cucumber were measured with a well-calibrated weighing lysimeter, from July to September 2021. The CU and Kc were obtained using CROPWAT 8.0. The Kc values for initial, mid and end stages of C. sativus growth were found to be (0.45-0.72); (0.71- 1.38); and (0.38 and 0.71) respectively for the two lysimeters. The seasonal crop water needed for the Cucumber (Cucumis sativus) was 422.32- 446.32 mm and the reference evapotranspiration increased from July to September from 5.31mm/day to 6.65mm/day.  The monthly CU of Cucumber was 228.6 mm/day in June, with an increasing reference evapotranspiration from 2.98 mm.day-1 in July to 3.18 mm.day-1 in August. The daily CU moved from 2.16 mm.day-1 in July to a peak of 4.03 mm.day-1 in August in the growing period. The monthly CU increased from 64.80 mm. month-1 in July to 120.90 mm. month-1 in August. All these are based on values obtained within the greenhouse. These findings offer a helpful guide for precisely applying water to places surrounding Ibadan and comparable agroecological characteristics.