Evapotranspiration and Crop Coefficient of Okra under Subsurface Drip with and without Plastic Mulch

Field experiments using lysimeters were conducted in sub-humid climatic condition to estimate water balance parameters, regional crop coefficient development and to evaluate yield response of okra crop under subsurface drip (SSD) irrigation with and without plastic mulch. In the year 2016, total crop evapotranspiration under SSD with and without plastic mulch was 403 and 512 mm respectively, whereas in 2017 it was 363 and 468 mm respectively. Average crop coefficient of okra was 0.31, 0.42, 0.68, 0.77 and 0.48 measured under SSD with plastic mulch condition, and 0.51, 0.72, 0.92, 0.93 and 0.53 without plastic mulch. High yield of okra with minimum crop evapotranspiration was observed under SSD with plastic mulch treatment due to lower irrigation water requirement, minimum evaporation and less weed transpiration under plastic film compared to nonmulch condition.