Evapotranspiration and crop coefficient estimation for a greenhouse garden of Heliconia bihai L.
This task was developed in screen greenhouse conditions at Curu-Paraipaba Experimental Station, coast region of
state of Ceará, Brazil and had as objective to estimate the evapotranspiration and crop coefficient for Heliconia bihai
L using the soil water balance method. The crop coefficient was estimated from either Penman-Monteith and Class
A pan evaporation ETo. The space used was 2.00 m between rows and 1.00 m between plants and they were
microsprinkler irrigated. The average daily evapotranspiration observed was 2.3 mm day-1, totalizing 174.7 mm for
the whole cycle. Regarding to the crop phase it was 2.2 mm day-1 for F2 phase ( 10% to 80% crop coverage), 2.3
mm day-1 for F3 phase (80% of crop coverage to blossom beginning) and 2.5 mm day-1 for F4 phase (blossom
beginning to harvest). The crop coefficients were higher when estimated by Class A pan evaporation ETo, when
comparing to those estimated by Penman-Monteith-FAO method. The results for F2 (beginning of water balance to
80% crop coverage), F3 (80% crop coverage until blossom beginning) and F4(from blossom beginning to harvest)
were 0,80, 1,20 e 1,20 respectively, for Class A pan evaporation and 0,60, 0,80 e 0,80 for Penman-Monteith-FAO.