Coeficientes de cultura (Kc) e crescimento vegetativo de ´Acaiá Cerrado´ (Cofeea arabica L.) associados a graus-dia (2º ano)

Abstract

Crop coefficients (Kc) for arabic coffee plants are usually related to days after planting or Julian calendar, not considering the variation in the developing rates of the crop for places and years. There is a tendency for using meteorological variables, that consider the climatic effect on the lasting of the developing phases of crop. This study had the objective of determine the crop coefficients (Kc) and vegetative growth of the coffee plant (Coffee arabica L.), cultivar Acaiá Cerrado, MG 1474, establishing a relation with the growing degree days (GDD). The work was conduced in the experimental area of the Department of Engineering of the "Federal University of Lavras" (UFLA), in the Lavras city (MG). The experience was composed by seven plots of different planting dates. The crop coefficients values were determined from the values of the reference evapotranspiration (ETo) and maximum crop evapotranspiration (ETc). Vegetative growth was evaluated and related to growing degree days (GDD). It was concluded that, in spite of the good adjustment between vegetative growth and growing degree days, there was effect of planting dates on the growth of the culture. That effect turns the utilization of the obtained adjusted model, not viable for other places. The obtained crop coefficients (Kc) curve for shows values from 0.7 to 1.2 for intervals of 700 GDD.