Abstract

PEREIRA, Hamilton Seron; BARBOSA, Newton Cabral; CARNEIRO, Marco Aurélio Carbone  and  KORNDORFER, Gaspar Henrique. Evaluation of sources and extractors of silicon in the soil. Pesq. agropec. bras. [online]. 2007, vol.42, n.2, pp. 239-247. ISSN 0100-204X.  http://dx.doi.org/10.1590/S0100-204X2007000200013.

The objective of this work was to evaluate silicon extractors and sources in the culture of the rice in a Quartzipsamment soil in a greenhouse. The experiment was completely randomized as a factorial design (26x7), comprising 25 silicon sources with 250 kg ha^-1 of Si applied, and the control, as well as 7 silicon extractors in the soil. Additional treatments with 125, 375 and 500 kg ha^-1 of Si were applied with wollastonite. Ninety days after sowing, the yielded dry matter of aerial parts and the soil and plant tissue Si content were determined. The source that provided higher Si absorption to the plants of rice was gel silicon, and the source that provided lower absorption was the MB-4. The extractors presented increased linear content of Si in the soil with the increment of doses of wollastonite. Among treatments, the high Si extraction ocurred with the acetic acid, and the calcium chloride went the extractor with better correlation. Ammonium carbonate and ammonium acetate presented near correlations to calcium chloride and had a larger distribution of the points, which better discriminated variations among the Si sources.

Keywords : Oryza sativa; slag; metallurgical aggregate; silicate.