Salt Leaching Mitigates Salinity Impacts on Sugarcane: Effects on Yield, Quality, and Economic Viability

Abstract Climate change has intensified water scarcity, increasing the use of saline water for irrigation. This practice may compromise the sustainability of salt-sensitive crops, such as sugarcane, which is essential for bioenergy production. A potential solution is to adopt management practices based on salt leaching. This study evaluated the effects of salinity on sugarcane yield, technological quality, and economic performance, as well as the mitigating potential of controlled leaching. The experiment was conducted at the Federal Rural University of Pernambuco (8° 01′ 06″ S 34° 56′ 49″ W), Brazil, using a completely randomized design in a 5 × 2 factorial arrangement with four replications. Five irrigation water salinity levels (0.5, 2.5, 4.5, 6.5, and 8.5 dS m⁻ 1 ) and two irrigation management practices were evaluated: without a leaching fraction (NLF) and with a leaching fraction (WLF) of 0.2. Crop yield, technological parameters, and economic indicators were assessed at harvest. The highest level of water salinity reduced stalk yield per hectare (25.23%), soluble solids content (9.93%), non-reducing sugars (15.19%), and total recoverable sugars (12.01%) but increased reducing sugars in the juice (34.95%). These effects decreased the industrial yields of sugars (− 36.00%) and ethanol (− 33.60%) and impacted economic indicators, leading to a reduction in net revenue of up to 78.06%. Controlled leaching increased the average net revenue by US$541.67 compared with conventional irrigation. It is concluded that controlled leaching was effective in mitigating salinity impacts on sugarcane cultivation.