EVAPOTRANSPIRAÇÃO, COEFICIENTE DE CULTURA E CRESCIMENTO DE CANA-DE-AÇÚCAR PLANTADA POR MUDAS PRÉ-BROTADAS E POR TOLETES

Abstract

Currently, the sugarcane presents several types of planting, especially the planting by pre-sprouted seedlings. This system needs new studies for the adequate recommendation of agronomic practices, such as irrigation. We aimed in this work to evaluate and compare the water consumption, crop coefficient and initial growth of sugarcane planted by pre-sprouted seedlings (PSS) and by stalks. Four treatments were defined, being sugarcane planted by PSS and by stalks, bahiagrass grass and bare soil, all kept in weighing lysimeters. The reference evapotranspiration (ETo) was measured in the grass lysimeters. The crop evapotranspiration (ETc) of sugarcane planted by PSS and stalks was estimated by water balance in the soil. The estimation of the crop coefficients (Kc) was obtained by the ratio between ETc of lysimeters with sugarcane and ETo. The comparison of the variables between planted sugarcane by PSS and by stalks was performed by regression analysis. The Kc of the sugarcane planted by stalks ranged between 0.86 to 2.88 and planting by PSS from 1.12 to 3.10. The sugarcane planted by PSS presents higher water consumption, crop coefficient and initial growth than when planted by stalks.