Water requirement of upland Taro (Colocasia esculenta) under humid tropical zones of India

Present study was carried out at the research farm of ICAR- Central Tuber Crops Research Institute, Thiruvananthapuram, Kerala during 3 summer seasons of 2016-17, 2017-18 and 2018-19 to assess the crop water requirement of upland taro (Colocasia esculenta L. Schott) and to arrive at a suitable irrigation schedule under humid tropical conditions of Kerala. The experiment was conducted in randomized block design (RBD), with 7 treatments as 5 levels of drip irrigation, [50% (I1), 75% (I2), 100% (I3), 125% (I4) and 150% (I5) of the crop evapotranspiration, ETc], furrow irrigation and a rainfed crop with 3 replications. Crop water requirement was calculated as same as crop evapotranspiration (ETc) assuming that there is no other water losses. Pooled analysis of the data collected for three seasons indicated that, I3, drip irrigation at ETc 100% is optimum for achieving maximum cormel yield and optimum water productivity. The optimal water requirement for upland taro was observed as 610-628 mm, including effective rainfall, based on the crop, soil and climatic parameters. The information will support the farmers to develop irrigation plans in advance during summer season, and for ensuring effective usage of irrigation water in water scarce areas, in this era of climate change.