Cultivo de tomate sweet grape em hidroponia com diferentes substratos utilizando água residuária

Abstract

The production of high value commercial vegetables such as tomatoes Sweet Grape, under protected substrates, provides greater efficiency of production factors that cultivation in soil. The aim of this study was to reuse wastewater enriched with nutrients and conventional nutrient solution, applied by drip irrigation in the cultivation of Sweet Grape tomatoes in pots with different substrates. The experiment was conducted at the State University of Goias - UnUCET between the months June to November 2011 in Anapolis, Goias The experiment was conducted in 3 x 2 factorial, randomized block design with four replications. The plots were made by the types of water (HA and FRC) and the types of substrate (S1 = 60% LA + 40%: 20% CF and 80% CP, S2 = 20% CF and 80% CP and S3 = FCN). The treatments were: T1 = S1 + AR, AR + S2 = T2, T3 = AR + S3, T4 = S1 + FRC, FRC + S2 = T5 and T6 = FRC + S3. The wastewater and well were analyzed for the following parameters: pH, electrical conductivity, temperature, dissolved oxygen, turbidity, alkalinity, total coliform and E. coli. For the quantitative analysis of residual water were also analyzed nitrate, nitrite, ammonium, potassium, manganese, total phosphate, sodium, total iron, total hardness, calcium, magnesium, chloride, sulfate, boron, zinc, copper, molybdenum, COD, BOD5 and total dissolved solids. We analyzed the amount of nutrients required to raise the salts present in the wastewater at levels similar to those used in conventional nutrient solution, and analysis of lower costs with nutrient economy. We evaluated the productivity, the diameter / length, the quantification of total coliforms and E. coli in tomato fruits. Determined to be titratable acidity (%), soluble solids (º Brix), the SS/TA ratio and pH. The irrigation system has been evaluated for application efficiency and distribution of the nutrient solution. The tension of water on the substrate was determined by a digital tensiometer puncture. The leach solution vessel was evaluated for pH, EC, nitrate and potassium. The data obtained in this study were subjected to analysis of variance by F test and mean comparison test (Tukey) at a significance level of 5%. The most significant results indicated that high temperature and RH did not affect the productivity and quality of tomato fruits. The production reached corresponding to 75% of the commercial tomato. The high amount of total coliforms present in RA did not affect the quality of tomato fruits. The use of wastewater has resulted in savings of nutrient trading. The index of uniformity of distribution of the nutrient solution at the end of the drip cycle were unacceptable in all treatments. The tension of water on the substrate was maintained within acceptable range for the cultivation of tomato mini. The values of electrical conductivity, nitrate and potassium in the leach solution rose along the cycle of mini tomatoes. The wastewater supplemented with nutrients can be applied for commercial cultivation in hydroponics with different substrates for the production of Sweet Grape