Extractors for iron quantification in soil cultivated with soybean - DOI: 10.4025/actasciagron.v26i3.1833

Abstract

The methodologies of micronutrientes analyses have been studied seeking a better expression of its texts in the soils and a larger adaptation to the analyses of routine of the laboratories. The efficiency of the extractors in the determination of the iron was evaluated through the use of acid extractors (Mehlich 1), in the relationship of 1:5 and 1:10, of an agent complexante (DTPA pH 7,3) and of combinated (Mehlich 3), in the relationship 1:10; the determination methodology consisted of agitation with immediate filtrate, filtrate after 16 hours of decantated and pipetate after decantação of 16 hours. The analyses included 18 representative soils of Paraná, collected to a depth of 0-20cm. The results they were appraised through the relationship among the concentration of the micronutrientes in the soil and concentration in the soy collected after 45 days of growth. There was equivalence in the extraction of the Fe of the soils for Mehlich 3, with immediate filtrate, Mehlich 1, with filtrate after decantação and DTPA; difference was not verified in the extraction of the Fe, when filtrate of the extract was made or when the solution was pipetate, after decantação of 16 hours; the highest texts of the nutrient happened in the soils Argissolo, Vertissolo and Gleyssolo and they were obtained with Mehlich 3, submitted to the decantated. Latossolos and Nitossolos, independent of the one of the extractor and of the analytic methodology, they presented the texts more bass of the iron