In the years 2000 – 2011 (12 years) was conducted weed survey on the farms in conventional farming system. The goal was to detect the most harmful weeds, as important biotic, environmental stress factor, on the farms in the canopies of sugar beet in maize and sugar beet production regions of the Slovak Republic. The fields were selected in maize and sugar beet production regions of Slovak Republic. An actual weed infestation was evaluated before preemergence application of herbicides. Screening of each field was made on 1 m 2 area with four replications. The four randomly established sample quadrants were situated minimally 20 m from field margin and apart from each other, respectively. The level of infestation was evaluated according to average density of weeds per square meter. Obtained data from farms was statistically analyzed by correlation analysis in Statistica 7.0. In the sugar beet stands 26 weed species were detected, the most problematic were: perennial weeds Cirsium arvense (L.)Scop. and Elytrigia repens (L.)DESV and annual weeds Atriplex spp., Amaranthus spp., Chenopodium spp., Echinochloa crus galli (L.)P.Beauv, Persicaria spp. and Datura stramonium (L.). Temporal dynamic of actual weed infestation depends on production region. After herbicides control the significant changes in weed flora were noted in term of abundance and share of some weed species on total weed community. Temporal dynamics of actual weed infestation depend on climate conditions of maize and sugar beet production region, fore crop and canopy health condition. Weeds are always a problem in sugar beet stands, because sugar beet plants are not so competitive, but control may be considered necessary to safeguard crop quality and yield. In spite of herbicides application, good timing of its application an actual weed infestation of sugar beet stands is high. The originality of result is in mapping the weed species and its actual weed infestation in cultural crops (sugar beet stands).

sugar beet, weed infestation, mapping

Presentation: oral