RESPONSE TO INCREASING DOSES OF LIQUID BOVINE MANURE BIOFERTILIZER IN LETTUCE CULTIVATION

Resumo

Liquid biofertilizers represent a renewable, low-cost, and effective source of nutrients for reducing chemical fertilizers, especially in short-cycle vegetables such as lettuce. The aim of the study was to evaluate agronomic variables of the crisp lettuce (Lactuca sativa L., cv. Vanda), produced using different doses of bovine liquid biofertilizer. The treatments consisted in foliar application of mineral fertilization and liquid biofertilizer, at the concentrations 0, 20, 40, 60 and 80%. The following parameters were evaluated: head diameter, total fresh mass of the aerial part, number of leaves, stem length, diameter and weight. The treatments with liquid biofertilizer showed significantly superior results compared to the treatment with mineral fertilization. The treatments with liquid biofertilizer (concentration of 20 to 80%) showed significantly superior results in relation to the treatment with conventional fertilization. By the technique of regression for quantitative variables, significant results were obtained, which indicated that the increase in the dose resulted in increment in the agronomic variables. The application of liquid bovine biofertilizer proves the possible substitution of mineral fertilizers in the cultivation of lettuce.