Estudo da evapotranspiração em cultura de feijoeiro (Phaseolus vulgaris L.).

Abstract

he water requirements of a dry beans crop (Phaseolus vulgaris L.) was detennined by measuring evapotranspiration with a constant water-table levei lysimeter, during a period of about 80 days (from november, 1982 to january, 1983), in Campina Grande, state of Paraíba, Brazil. The values of reference evapotranspiration (ETQ) for the same period, were estimated according to the Penman, Hargreaves, Radiation and "USWM class A land pan" approaches. The results of both, empirical and experimental methods, were utilized to estimate the correspondent crop coeficients (Kc) in different phases of the crop cycle and compared with the FAO re commended values of Kc. The statistical analysis show that the Kc estimatives according to "USWB class A land pan" approach are nearer to theFAO values.