Resíduo de terra diatomácea utilizado como suplementação nutricional na compostagem para a cultura da alface

Abstract

Due to the increasing world requirement for solid and liquid wastes generated by industries and agricultural activities, which are often disposed without proper treatment, wastes manufacturers companies have searched for alternatives to their reusing. Among these possible reuses, the use of diatomaceous earth waste arise as an alternative to beer and soda factories as nutritional supplementation which could be used in composting. In this way, the objective of the work was to verify the best management to provide N for the lettuce crop through different chemical and organic sources, evaluating the parameters of productivity, mineral nutrition of plants, conservation and quality of the crop.The experiment was developed at ETEC Prof. Luiz Pires Barbosa in Cândido Mota city, São Paulo state, sited in the countryside, during the period from April to December, 2017. The experimental design was held in randomized blocks with six (6) treatments and four (4) repetitions. The treatments were: T1 = 100% nitrogen (urea) (coverage) Witness; T2 = 50% urea (coverage) and 50% of organic compound; T3 = 100% organic fertilizer; T4 = 50% cattle manure and 50% urea (coverage); T5 = 100% cattle manure, T6 = 50% cattle manure and 50% organic compound. At the end of the cycle in central rows, the internal and external diameters, fresh and dry substance mass of the aerial part, content, nutrients exportation and shelf life were evaluated. Comparing the tested treatments, T5 (100% cattle manure) was the one which showed a higher fresh mass production (g), followed by T4 (50% cattle manure and 50% urea) and T2 (50% urea (coverage) and 50% organic compound), regarding to chemical fertilization in two consecutive cycles. Concerning to storage days related to shelf life testing of treatments with different fertilization types, appearance and withering were not evidenced.