The research was carried out to evaluate the growth and components of production of the castor bean cv. BRS Energia under different levels of salinity of the irrigation water (CEa) and nitrogen doses under field conditions in an eutrophic Usthorthent of sandy loam texture in the municipality of Pombal, PB. The experimental design consisted of randomized blocks, testing five levels of salinity of irrigation water - CEa (0.4-control, 1.4, 2.4, 3.4 and 4.4 dS m-1) and five N doses (50, 75, 100, 125 and 150 mg kg-1) in a 5 x 5 factorial scheme with three replications. The increase of CEa from 0.4 dS m-1 reduced the number of leaves (NF), plant height (AP), stem diameter (DC), dry mass of the shoots (MSPA), cluster length (CRP), effective cluster length occupied by female flowers (CREFF), total number of seeds in primary cluster (NSRP) and total seed production (PSemT) of the studied castor bean cultivar. The interaction between water salinity and nitrogen dose for NF, DC, MSPA, CRP and CEes - electrical conductivity of the saturation extract of the soil was significant while the increase of nitrogen doses reduced the negative effects of salinity up to the level of 2.4 dS m-1. The CEes increased with increase in CEa and nitrogen doses.
Ricinus communis; saline water; nitrogen
