Effect of Fertilization and Weed Management on Weed Flora of Hemp Crop

Hemp is known to have a competitive advantage over weeds. Despite its suppressive ability, weed infestation remains an important issue during the early growth of the crop. The aim of this study was to determine the effect of fertilization and weed management on weed flora and hemp growth parameters during initial growth in the 2019 season. The experiment was laid out in a split-split plot design with three replicates: three hemp cultivars as main plots, three fertilization treatments as sub-plots and two sub-sub-plots (weedy, weed free). For the computation of height and biomass weight, 10 plants were randomly selected in each plot. Weed species were collected by quadrate and density and biomass weight were determined. ANOVA revealed that all factors and their interactions significantly affected plant traits. Hemp cultivars showed different competitive ability. ‘Futura 17’ reduced weed measurement traits better than ‘Uso 31’. Density and biomass of nitrophilous weeds increased with the higher N dose compared to control (up to 56% and 79% respectively), therefore negatively affecting the growth of the hemp plants. Further research is needed in order to identify useful information on interactions between weeds and hemp crop to address potential yield losses under different weed management systems.