Sorption and Degradation of Selected Fungicides in the Turfgrass Canopy

摘要: Microbial degradation of fungicides on leaf surfaces after repeated applications to turfgrass was investigated. Prior andcurrent work in our laboratory has identified two characteristicsof the system that may contribute enhanceddegradation application turfgrass:(1) The surface is rich microorganisms (∼108 g-1 dr wt leaf), and (2) Leaf respond fungicide a manner consistentwith phenomena enhanced biodegradation. Field studies wereconducted ‘Penncross' creeping bentgrass with four fungicidesrepresenting three chemical families applied either or eight times one growing season. Biodegradation estimated using data from both field study parallel thatfollowed fate 14C-labelled fungicides. For incubations, locations residual 14C were sequential extraction protocolthat fractionated materials into pools: available,retained bound. Data studyrefuted hypothesis biodegradation would developfollowing onto leafsurface. Our support conclusion two-stagephysical sorption process leads plant incorporation thiscontrols most fungicide's fate. Thus, suggestthat microbial activity plays less important part theprocess than be indicated by considering size themicrobial population leaves.