Macronutrient cycling in hydroponic lettuce cultivation

In order to address issues of limited resources and contamination by fertilizers, nutrient solutions may be reused in hydroponics as an alternative their disposal the environment. This work evaluated feasibility replacement for during lettuce hydroponic cultivation. The experiment was carried out agricultural greenhouse NFT system using “Milena” cultivar. divided into two stages: 1) monitoring data collection proposition management; 2) validation proposed management. Monitoring consumption crop's nutritional solution first stage served basis Management validated second through evaluation fresh dry mass, crop status, amount fertilizer applied treatments: T1 - with reuse; T2 without reuse. mass nutrients absorbed plants were submitted t-test at 5% probability, showing no significant difference between treatments, making it possible conclude that reuse provided cultivation.
 Keywords: system, Lactuca sativa L., macronutrient rational use.