Publicação on-line; 32 ref.; 2 tables; 6 illus.; Summary (En)

ABSTRACT
Background: Weed control in the pre-harvest of the coffee crop is
essential to enable mechanized coffee harvesting.
Objective: Testing the efficacy of pre-emergent herbicides, applied after
brush shredder or desiccation operations, on the weed control during the
coffee crop’s pre-harvest.
Methods: Two separate trials were accomplished in commercial Coffea
arabica crops in the Cerrado Mineiro Region. In the first one, oxyfluorfen
and sulfentrazone were applied after either brush shredder or burndown
operation; in the second, they were tested as a tank mixture with
glyphosate.
Results: In the first assay, the brush shredder use, associated to the
rains that follow, stimulated a sharp weed infestation during the preharvest,
which was not observed in desiccated plots. A sole application
of oxyfluorfen or sulfentrazone, following either brush shedder or
desiccation operation, effectively controlled the weeds; however, the
sequential applications on burndown areas may be needless. The applied
herbicides did not intoxicate the coffee plants nor affect their growth. In
the second assay, both herbicide mixtures were highly efficient on the
weed control through post-emergence application during the pre-harvest,
what was not observed with a sole application of glyphosate. In both
experiments, a dry period during winter, associated to the operations to
gather fallen coffee fruit, collectively contributed to control weeds.
Differently from oxyfluorfen, the residual effect of sulfentrazone was high
enough to control weed even in the beginning of the rainy season.
Conclusion: Sulfentrazone and oxyfluorfen were effective on the weed
control in the pre-harvest of the coffee crop, mainly when applied after
brush shedder operations

Keywords:
Coffea arabica
burndown
herbicide
integrated weed management