Planting time and irrigation management for castor plant. I – effect on yield components

Abstract

The association or early planting of castor bean with irrigation practice can improve yield components such as the number of racemes per plant and capsules per racemes. The purpose of this work was to investigate the effect of various sowing time and supplemental irrigation on the yield components of the castor oil plant. The experiment was carried out at the experimental farm Vale do Curu, at the Pentecoste, Ceará, Brazil. Standard cultural practices of soil preparation and fertilization were used. Seeds of castor plant cv. BRS Nordestina were planted in rows spaced of 1.5 m x 1.0 m, with one plant per hill. The experimental design was arranged in a randomized block with eight treatments and four replications. The treatments were composed of four sowing times and several irrigation managements. The early planting at January with the use of irrigation increased the size and number of racemes per plant, and the weight and number of capsules per racemes. The secondary and tertiary racemes produced seeds with higher oil content and seed weight, as compared to the primary racemes. High positive correlation was found between seed yield per plant and number of the racemes per plant. The weight of racemes was positively correlated with the number of fruits per raceme.