Bovine biofertilizer and irrigation layers on lettuce development and leaf chlorophyll/Biofertilizante bovino e laminas de irrigação no desenvolvimento e clorofila foliar da alface

It is necessary and urgent the search by sources of an organic fertilizer and decrease the consumption of water for irrigation. In the context, the aim of this study was to evaluate the nutritional effects of the use of bovine biofertilizers incorporated into the soil and of the irrigation in the development of lettuce. The research was developed, using an experimental design in randomized blocks, factorial scheme 6x2, with six levels of fertilization and two irrigation layers (80 and 100% of reference evapotranspiration) with four replications, in the field. The variables analyzed were: height, head diameter, chlorophyll, leaf number, fresh matter and dry matter of plant tops. It was performed by analysis of variance of F test, comparison of means by Tukey test and polynomial regression. The results showed that the levels of biofertilizer were similar to the mineral control, pointing the possibility to replace them with the dose of 90m3ha-1 more recommendable, and the best water layer, of 80% of the evapotranspiration.