Crop water requirement (ETc) of Maize crop of Panchmahal Region of Gujarat

Abstract

Accurate estimation of crop water requirements (ETc) of any crop is essentially for irrigation scheduling and water management. The present study was undertaken to estimate the crop water requirement (ETc) of maize crops grown in winter seasons in middle Gujarat region of Panam command area Gujarat. The daily reference evapotranspiration (ETo) was estimated by FAO Penman-Monteith method using 11 years (2006 to 2016) mean meteorological data of Panam command. The most common and practical approach widely used for estimating crop water requirement, and the operational monitoring of soil-plant water balance is the FAO-56 method. In the FAO-56 approach, crop evapotranspiration is estimated by the combination of a reference evapotranspiration (ETo) and crop coefficients. The Kc values for maize as given in FAO-56 was used in which Kcmid and Kcend were corrected for climatic conditions of stations. The corrected Kc values were used to calculate the daily crop water requirement (ETc) for maize crops grown at Panchmahal region. The results revealed that during winter season (15 October to 15 January) the mean daily (ETo) varies from 5.5 to 7.32 mm day-1. The mean water requirement of maize during initial stage is 1.085 mm day-1, during developmental stage it varies between 1.085 to 4.35 mm day-1, and during the mid-season stage ETc varies between 4.35 to 5.76 mm day-1 and during late season stage it decreases upto 3.20 mm day-1. The seasonal water requirement of winter maize varies between 312.49 mm to 487.08 mm. This study established precise estimation of evapotranspiration which was the only beneficial water loss from the field. The information generated can be used in scheduling irrigation for winter season maize crops of Panchmhal region.