Yield and nutritional quality of castilla bean (Vigna unguiculata L. Walp) under the application of liquid organic fertilizers

Objective: To determine the effectiveness of liquid fertilizers on Vigna unguiculuta under field conditions. Design/methodology/approach: Treatments were applied in a randomized block design: bovine biol (at 5 and 10%), earthworm leached (at 25 and 50%) and compost tea (20 and 40%), as well as a control with chemical foliar fertilizer and a water control. The performance variables evaluated were plant height (cm), days to flowering (days), grain yield (g/plant; kg/ha), weight of 100 seeds (g), plant dry matter (kg/ha), NPK in grain and stems-leaves (%), and the percentage of crude protein of the harvested bean; most of the variables were measured until harvest. Results: The results suggest that bovine biol at 5% and 10% and worm leached at 25% and 50% are the treatments that showed to be the best candidates for grain yield with 640.30 kg ha-1, 582.39 kg ha-1. 1,519.68 kg ha-1 and 509.73 kg ha-1 respectively, showing to be higher to the chemical treatment (373.77 ha-1) and absolute treatment (352.49 ha-1). The 25% and 50% worm leached treatments showed greater NPK absorption compared to the other treatments, which influenced a higher crude protein content in the harvested biomass. Limitations on study/implications: In La Chontalpa region of Tabasco, Mexico, the cultivation of V. unguiculata has been abandoned by small producers due to the decrease in their yields, caused mainly by poor agronomic management. Liquid organic fertilizers are eco-friendly foliar fertilization alternatives with proven effectiveness in various crops, totally or partially replacing the use of chemical fertilization. Findings/conclusions: The general results suggest that using bovine biol or worm leached in the concentrations evaluated as foliar fertilizer in V. unguiculata will increase the yield and nutritional quality of the crop compared to chemical fertilization.