Nanoengineered Sorbents to Increase the Persistence of the Allelochemical Carvone in the Rhizosphere

8 páginas.-- 4 figuras.-- 2 tablas.--50 referencias.-- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jafc.8b05692.

This study investigates the changes in sorption/desorption, dissipation, and leaching of the two enantiomeric forms of the allelochemical carvone, R-carvone and S-carvone, after amending an agricultural soil sample with two nanoengineered sorbents: biochar (BC) and organoclay (OCl). The sorption of carvone enantiomers was nonenantioselective and similarly improved by the addition of OCl and BC to the soil. However, OCl-amended soil showed reversible sorption, whereas BC-amended soil displayed sorption-desorption hysteresis. Dissipation of carvone enantiomers was enantioselective. Both amendments increased the half-life of the enantiomers in the soil. This effect was more pronounced for BC-amended soil and for S-carvone. Leaching of R- and S-carvone through soil columns was scarce in unamended soil (<7%), due to their rapid degradation during leaching, and null for OCl- and BC-amended soil, for which much of the applied R- and S-carvone remained in the top 0-5 cm of the amended soil layer. Addition of biochars and organoclays could help increase the persistence of carvone enantiomers in the rhizosphere, which may favor their use as residual pest-management substances

This work was financed by the Spanish Ministry of Science, Innovation and Universities (MICINN Project AGL2017-82141-R). B.G. would like to thank MICINN for her Juan de la Cierva-Incorporación postdoctoral contract (IJCI-2015- 23309).

Peer reviewed