SILVA, S. S.; http://lattes.cnpq.br/3048098827488041; SILVA, Saulo Soares da.
Resumen:
Castos is an oilseed crop belonging to the family Euphorbiaceae, with significant
socioeconomic vague, with products and coproducts ricinoquimica used in industry and
agriculture, which has great economia potencial 6or the semi-arid northeastern Brazil. The
objective of this research was to evaluate the et6ect of diflêrent salinity leveis of irrigation
water associated with nitrogen fertílization on the castos bean cv. BRS Energy, grown in
lysimeters under field conditions. We adopted the experimental design of randomized blocks,
arranged in a 5 x 5 factorial design with three replications and the treatments consísted offive
leveis ofelectrical conductivity of irrigation water - ECw (0.4, 1.4, 2.4; 3.4 and 4.4 dS m ')
and teve doses of nitrogen (50, 75, 100, 125 and ]50 % ofthe indication ofnitrogen 100 mg
kg ' ' for testing in pot) . From the salinity ofthe irrigation water of 0.4 dS m ' ' were linear
decreases in the percentage of emergency, the index of germination speed, number of leaves,
plant height and stem diameter of castor bean. Increasing leveis of nitrogen attenuated the
effect of salinity of irrigation water to the levei of 2.4 dS m ' ' promoting higher specifíc leaf
área of the castor. The number of seeds of the pastor bean primary raceme was the variable
most sensitive to salt stress, resulting in reduction respectively of 1 8.3 % per unit increase in the electrícal conductivity of irrigation water. The interactíon between salinity and N leveis was significant for number of leaves and stem diameter, with increasing doses of nitrogen mitigated the negative ef6ect of water salinity to the levei of 2.4 dS m ' '. The electrical conductivity of írrigatíon water up to 1.9 dS m - l and nitrogen from 134 % of the recommended favor greater number of racemes per plant.