Biofertilizante como solução nutritiva para produção de alface hidropônica no Alto Sertão paraibano.

The use of hydroponic systems by family farmers in the Paraiba semiarid region allows a continuous production of vegetables due to the water limitations typical of this region. However, the difficult access and the high cost of mineral fertilizers is a limiting factor of this practice. In this sense, the objective was to evaluate the potential of the use of bovine anaerobic biofertilizer in the substitution of mineral fertilizers, in the cultivation of lettuce group cv. Cristina. The work was conducted in a greenhouse, installed at the Federal Institute of Paraíba, Campus Sousa. Four doses plus mineral fertilizers were evaluated: Bio + 0%; Bio + 25%; Bio + 50%, Bio + 75%, with four repetitions, in randomized blocks. Leaf dry mass and total mass, total number of leaves, leaf area and yield were evaluated. The reduction of the mineral fertilizer doses compromised the growth and consequently the lettuce production, where the maximum production of the commercial part was 43.0 g plant-1, being obtained with the treatment of 75% of the combination of the most mineral fertilizer doses. Biofertilizer. [ABSTRACT FROM AUTHOR]