The use of cow urine can be considered an agricultural practice of low cost for farmers. Nevertheless, its efficiency on crop needs research information. The present research aimed to evaluate the effect of cow urine on the growth and yield of 'Regina 2000' lettuce, in an experiment carried out from January 13, 2006 to March 22, 2006. The experiment was set up with 12 treatments, in a split-plot design and four completely randomized blocks. The soil and leaf applications were installed in the plot. In the split-plot, cow urine was applied at different concentrations (0.00; 0.25; 0.50; 0.75; 1.00 and 1.25 %). The plot presented four rows with 1.75 m each, in 0.25 x 0.25 m spacing. The six central plants of the two central rows formed the sampled split-plot. At harvest, the following variables were evaluated: fresh (FLM) and dry (DLM) leaf mass, fresh (FSM) and dry (DSM) stem mass, stem length (SL), fresh (FRM) and dry (DRM) root mass, fresh (FHM) and dry (DHM) head mass and commercial yield (CY). The increase in cow urine concentrations increased the performance of all lettuce characteristics, except DRM, which presented reduction, and DSM and FRM, which were not affected. The highest yield was obtained with the concentration of 1.25% (17.00 t ha-1) applied to leaves and with 1.01% (14.92 t ha-1), applied to soil, corresponding, respectively to increases of 28.1% and 47.3%, in comparison to the control. Application to leaves, in comparison to application to soil, resulted in greater FLM (0.50 and 1.25%), SL (0.50; 0.75 and 1.25%), FSM and FRM (0.5%), FHM and CY (0.50 and 1.25%), but lower DSM and FRM (1.25%) and DRM (1.0 and 1.25%). The application of cow urine solution at 1.25% to leaves or 1.0% to soil is recommended for lettuce crops.
Lactuca sativa; plant growth; biofertilizer
