SILICIO DISPONIBLE EN SUELOS ALCALINOS POR DIFERENTES MÉTODOS Y EL ABSORBIDO POR CULTIVOS DE MAIZ Y FRIJOL A NIVEL DE INVERNADERO

Extracción de silicio en suelos alcalinos

Abstract

Silicon (Si) is a beneficial element for different crops that are currently being studied. The objective was to evaluate the available silicon extracted with four chemical extractors in alkaline soils and its correlation with that extracted by maize and cowpea bean crops. The experiment was carried out at the Faculty of Agricultural Sciences of the University of Córdoba. A completely randomized design with factorial arrangement, 2x3x4 (two cultures, three alkaline soils and four repetitions) was used. The extraction methods were: calcium chloride (0.01 mol L^-1), acetic acid (0.5 mol L^-1), ammonium acetate to 38.5 g L^-1 and the method proposed by the authors called modified water. The variables evaluated were the content of Si extracted from the soil by different methods and the Si in the leaves. Quantification was performed in a spectrophotometer at 660 nm and the data were analyzed with analysis of variance and correlation. The results indicate that the most effective method to extract silicon from alkaline soils for the cultivation of beans and corn was the 0.5 mol L^-1 acetic acid method and the one that extracted the least was 0.01 mol L^-1  calcium chloride. Furthermore, CaCl2 0.01 mol L^-1 and the method proposed by the authors may be an alternative for use in estimating available silicon in alkaline soils. The silicon absorbed by the cultures and the one extracted by the methods depends directly on the indicator species and the extractor used.