EVALUATION OF IRRIGATION LEVELS IN THE CASTOR BEAN (Ricinus communis L.) IN THE BRAZILIAN SEMIARID REGION

Resumo

There has been an increase in the search for forms of renewable energy with lo environmental impacts, of which biodiesel is highlighted. The castor bean (Ricinus communis L.) is a major raw material for the derivation of these biomass-based fuels. Due to the lack of information in literature regarding irrigation in castor bean crops in the semiarid region of Bahia, the aim of this study was to evaluate different irrigation levels on growth and yield of castor beans in the semiarid region of Bahia. The study was conducted in an experimental area of the agricultural sector of the Federal Institute of Education, Science and Technology Campus, Guanambi, Bahia, Brazil. The experiment was setup in a completely randomized design with 4x5 factorial scheme, consisting of four irrigation levels (T1: 100% ETc, T2: 80% of ETc, T3: 60% of ETc and T4: 40% of ETc, with drip irrigation), five evaluation dates (65, 80, 95, 110 and 126 day after sowing) and four replications. The reduction in irrigation did not cause differences in plant height, stem diameter and crown diameter of the castor bean cultivar Paraguaçu. Irrigation at 80% ETc showed to be more suitable, with increased yield and water use efficiency.