Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effects of soil attributes and straw accumulation on the sorption of hexazinone and tebuthiuron in tropical soils cultivated with sugarcane

Full text
Author(s):
Pereira-Junior, Ernani V. [1] ; Giori, Fabricio G. [1] ; Nascimento, Altina L. [1] ; Tornisielo, Valdemar L. [2] ; Regitano, Jussara B. [1]
Total Authors: 5
Affiliation:
[1] Univ Sao Paulo, Coll Agr Luiz de Queiroz, Dept Soil Sci, ESALQ USP, BR-13418900 Piracicaba, SP - Brazil
[2] Univ Sao Paulo, Ctr Nucl Energy Agr, Ecotoxicol Lab, CENA USP, Piracicaba, SP - Brazil
Total Affiliations: 2
Document type: Journal article
Source: JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART B-PESTICIDES FOOD CONTAMIN; v. 50, n. 4, p. 238-246, APR 3 2015.
Web of Science Citations: 6
Abstract

Brazil is the largest sugarcane producer in the world in which hexazinone (3-cyclohexyl-6-dimethylamino-1-methyl-1,3,5-triazine-2,4-dione) and tebuthiuron (1-(5-tert-butyl-1,3,4-thiadiazol-2-yl)-1,3-dimethylurea) are heavily used. Sugarcane harvesting is changing from the manual system with previous straw burning to the mechanized system without straw burning. The lack of burning results in soil organic carbon accumulation mainly in clayey soils, which should affect herbicides availability and fate. Therefore, we evaluated sorption of these herbicides in soil samples with and without straw burning. Both herbicides presented low apparent sorption coefficients (mean K-d,K-app= 0.6 and 2.4 L kg(-1) for hexazinone and tebuthiuron, respectively), suggesting that they may leach to groundwater. Moreover, their sorption correlated primarily with soil organic carbon (SOC), but iron oxide contents extracted with ammonium oxalate (Fe2O3AOX) also affected it (K-d,K-app = -0.228 + 0.0397 SOC + 0.117 Fe2O3AOX for hexazinone and K-d,K-app = -1.407 + 0.201 SOC + 0.348 Fe2O3AOX for tebuthiuron). Soil organic carbon accumulation due to straw maintenance in the field positively affected sorption of both herbicides, but its effects were not enough to classify them as ``non-leachers.{''} (AU)

FAPESP's process: 12/15843-0 - Harvesting systems (with and without residue burning) on the sorption and desorption of herbicides in sugar cane
Grantee:Jussara Borges Regitano
Support Opportunities: Regular Research Grants