Saline water as an alternative for irrigation of sorghum for energy generation in northeast Brazil

Abstract

The objective of this study was to evaluate the production of stalks, dry water total, sugar, ATR and energy (biomass and ethanol) of sorghum cultivars (BRS 506 and Ponta Negra) submitted to different saline concentrations of irrigation water (0.8, 2.4, 3.4, and 4.8 dS m^-1) and irrigation depths (306, 378 and 490 mm). The factors studied were arranged in subdivided plots (4x3)x3, with saline concentrations and depths slides in factorial and the cultivars in the subdivided plots, delineated in randomized blocks with four replicates. It was observed a reduction of 16% for the variables stalks yield and energy from depth 306 mm to 490 mm (exceeding 23% of the depth considered potential for crop). Only BRS 506 showed a reduction of ATR (19.8%), yield of sugar (19.8%) and stalks (11.0%) when irrigated with water of 4.8 dS m^-1 in relation to water of 0.8 dS m^-1 . The sorghum cultivar Ponta Negra presented higher dry matter total and energy in relation to cultivar BRS 506 in all saline concentrations studied, the cultivar BRS 506 showed higher sugar yield, ATR and ethanol in relation to the Ponta Negra cultivar.