Uso de efluente proveniente de uma indústria de sorvete no cultivo hidropônico de tomate cereja.

Abstract

Agriculture is an activity that consumes the most water and plants to supply shortages in the use of wastewater can be a viable alternative not only in terms of water supply, but also to supply them chemically with nutrients. The tomato is the second most widely grown and consumed vegetables in Brazil. Among the essential nutrients, potassium is the nutrient most absorbed, followed by nitrogen and calcium. However, calcium when in deficit levels can cause damage of up to 50% in fruit production. The purpose of this study was to evaluate the feasibility and implications of the use of effluent from an ice cream industry in the hydroponic cultive of the cherry tomatoes as an alternative to soluble fertilizer. The experimental design was completely randomized design with six treatments and four replications. The treatments included the use of effluent doses (0,25, 50, 75 and 100%) with supplementation of nutrients and using 100% effluent without nutrient supplementation. The nutrient solutions were applied throughout the crop cycle (126 days) with the use of hydroponics NFT type with recirculation. It was concluded that the wastewater provided differences in water consumption because of the different levels of effluent added to the nutrient solution. Treatment with 25% with effluent provided the best productivity. The addition of up to 50% of ice cream to the effluent nutrient solution allows the cultivation of cherry tomatoes without reducing productivity, with improved efficiency of water use in dry matter production of shoots, fruit production and maximum replacement of soluble minerals in the nutrient solution. There were changes in the absorption of nutrients with increasing doses of effluent. The fruits produced showed coliform levels well below the standards recommended by the sanitary brazilian norms.