Estimation of water requirement of Banana crop under drip irrigation with and without plastic mulch using dual crop coefficient approach

Field experiments were conducted on the lateritic sandy loam soil and sub-humid climate of Kharagpur, West Bengal, India during 2014-2018 for two consecutive crop seasons to determine the optimum water requirement of the Banana crop under drip irrigation with and without plastic mulch. Reference evapotranspiration for the Banana crop was estimated using FAO-56 Penman-Monteith approach. The dual crop coefficient approach was used to improve the estimates of the crop coefficient (K-c) values for the irrigation treatments with black plastic mulch and without mulch. Plants treated with black plastic mulch consume about 12% less water for the main crop and about 22% less water for ratoon crop compared to non-mulch plants. The effect of black plastic mulch was studied to determine the soil moisture distribution in different soil depths (0-20, 20-40, 40-60, and 60-90 cm), and also loss of water through deep drainage. Net irrigation requirement under black plastic mulch was found to be lesser than without mulch. The deep percolation was found 50.4 % more under black plastic mulch in comparison to non-mulch treatment.