Evaluation of microbiological and sanitary hydroponic lettuce grown with recycled water

Abstract

Population growth, and hence the need to increase food production lead to increased exploitation of natural resources, especially water. The challenge for humanity in relation to this natural resource is to rationalize its use, and maintain quality solutions for the treatment and reuse. Within this context hydroponics, which is growing plants without soil , can be an alternative technique for water reuse , since they have the advantage of minimizing contact between the wastewater , the edible parts of plants and farmers because only the plant's root system has direct contact with the water. The present study aims to assess the microbiological quality and health of lettuce (Lactuca sativa L) grown in hydroponics system using recycled water from Pilot Station Sewage Treatment. The experiment will be performed Agricultural Science Center - UFSCar in Araras, SP, in a greenhouse. The crop will be from february to april 2014. The hydroponic system adopted is the technique of Laminar Flow of Nutrients (NFT), are the first two treatments with water supply and commercial nutrient solution, the second with sewage treated and supplemented with commercial nutrient solution according to results of chemical analysis prior. Each treatment will consist of four benches (repetitions), a reservoir of 500 L to store the nutrient solution, a set bike pump and a timer. The holes in the profiles are 0.057 m in diameter to allocate the seedlings every 0.25 m of the profile, totaling 12 plants per profile, 48 bench and 192 plants per treatment. The results will be discussed and compared in terms of quality as sanitary legislation in Brazil regulated by RDC No. 12, dated January 2, 2001 and approved by the Secretary of Health Surveillance - SVS Ministry of Health The parameters used are the without E. presence coli and fecal coliform maximum of 102 grass - 1 . It is hoped that this work contribute to the research on water reuse in agriculture and point hydroponics as an alternative for safe application of this water.