Viabilidade do cultivo hidropônico de genótipos de alface com soluções minerais e organominerais otimizadas.

Abstract

Currently, the quality of the food has been considered as a safety food and nutrition factor. It is related not only for the production of food in sufficient quantity and guaranteed access but also to promote the health of those who consume it.Due to the described the objective of this work was to technically and economically evaluate the cultivation of lettuce grown hydroponically with mineral and organomineral nutrient solutions optimized through SOLVER tool of Microsoft Office Excel. The experiment was conducted at the Center for Agricultural and Environmental Sciences of the University State of Paraíba in two stages. Firstly, we evaluated the growth and production of three lettuce cultivars in floating system adopting a comp+++++letely randomized design arranged in a factorial 4 x 3 with three replications.The factors were 4 nutrient solutions (S1 = 100% mineral solution; S2 = 90% mineral solution + 10% organic solution; S3 = 84% mineral solution + 16% organic solution and S4 = 78% mineral solution + 22% organic solution) and 3 lettuce cultivars (C1 - Leaf; C2 – Butterhead, and C3 - Ruby). During the conduct of the experiment were monitored and calibrated the electrical conductivity (EC) and the potential of hydrogen (pH). After 25 days of germination we assessed the growth and yield parameters of the plants. At this stage, there were not lettuce visual symptoms of nutritional deficiency and toxicity independently of the solution and lettuce variety studied, this result led to the completion of the second stage of the experiment that was to formulate and to test organomineral solutions with the same chemical composition of mineral solutions commonly cited in the literature. To do this were set up an experiment in triplicate and in a randomized block with split plot using thenutrient film technique (NFT) system. The plots corresponded to eight nutrient solutions with four minerals with composition suggested by Bernardes, Furlani, Castelane&Araújo, Ueda and four organomineral solutions with the same composition as the aforementioned. The subplots were composed of three varieties of leaf lettuce: Thais, Vanda, and Veronica. During the experiment, the EC parameters, pH, consumption and temperature of nutrient solutions were monitored daily for 24 days. After this period we assessed the growth parameters, production, parasitological quality, and microbiological quality of the product, as well as the economic analysis of lettuce produced by the treatments.The organomineral solutions presented more resistance to changes in pH, however, lower yields were obtained compared to mineral solution. Results of microbiological and parasitological quality on the samples of lettuce analyzed showed no contamination by E. coli and Salmonella, regardless of nutritious solution, according to standards set by the National Health Surveillance Agency - ANVISA.The growth hydroponic of lettuce proved to be a profitable activity. However, according to the simulation performed, the loan discharge ranged for the choice of solutions being impracticable only the use of organomineralsolutions Castelane&Araújo, Bernardes and Ueda.