Effect of liquid cattle manure and inorganic fertilizers on tomato yield and water use in a hydroponic system
The use of liquid manure as a source of nutrients and water in agricultural production decreases environmental pollution and leads to economic savings for farmers. We compared the use of liquid cattle manure extract (LCME) and chemical fertilizer in nutrient solution, plus their respective water use efficiency index, in tomato (Licopersicon esculentum Mill) production in a hydroponic greenhouse system. Three factors were assessed at two levels: raw and fermented LCME; electrical conductivity (EC) of two solutions (2 and 4 dS∙m-1); and the addition of chemical fertilizers to supplement the LCME solutions. Two treatments with inorganic fertilizers (Steiner’s solution) were added to each EC level as controls. A total of ten treatments were evaluated in a factorial arrangement (23) with eight replications. Results showed higher dry matter (133.9 g∙plant-1) and yield (2,742 g∙plant-1) values in plants irrigated with nutrient solutions with EC of 2 dS∙m-1. The fermented and fertilizer-supplemented LCME solutions had the same behavior as the raw LCME without fertilizers in tomato plant growth and yield in a hydroponic greenhouse system.