Weed communities in the organic cultivation of fresh maize intercropped with legumes and coffee husk

The objective of this study was to evaluate the phytosociology of the weed communities in maize intercropped with legumes and coffee husk in an organic production system, emphasizing on the relative importance of the weeds and their biomass. The experiment was implemented with the following treatments: T1 - Maize intercropped with Phaseolus vulgaris and weed mowing, T2 – maize intercropped with Crotalaria juncea and weed mowing, T3 - Maize intercropped with Canavalia ensiformis and weed mowing, T4 - Maize intercropped with Cajanus cajan and weed mowing, T5 - Maize grown on soil covered with coffee husk (100 m3 ha-1) and manual weeding and T6 - Maize grown under conventional tillage system and manual weeding (control). The treatments were performed under a random block design with five replications each. A phytosociological analysis of the weeds was performed at stages V4, V8, and R1 to determine the relative importance (RI%) and biomass. The lowest biomass (11.6 g m-2) of weeds occurred when maize was grown on soil covered with coffee husk. In total, 13 species of weeds were identified, being Cyperus rotundus L. the most prevailing species (%). From this study, it was determined that growing maize on soil covered with coffee husk is an alternative to suppress weeds in the organic fresh maize system when coffee husk is available.