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 pea for grain in maize, sugar beet and potato production regions of the Slovak Republic. The fields were selected in all production regions of Slovakia. 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 pea for grain canopies 10 most dangerous weed species were detected, the most problematic were: perennial weeds Cirsium arvense (L.) Scop. and Elytrigia repens (L.) DESV and annual weeds Atriplex spp., Avena fatua L., Amaranthus spp., Anthemis spp., Chenopodium spp., Tripleurospermum perforatum (Mérat) M. Lainz, Echinochloa crus galli (L.) P. Beauv 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, sugar beet and potato production region, forecrop and pea stand health condition. Spring and perennial weeds are always a problem in pea for grain stands, because pea plants are not so competitive, but control may be considered necessary to safeguard crop quality and yield. The originality of result is in mapping the weed species and its actual weed infestation in cultural crops (pea for grain stands).

pea for grain, weed infestation, mapping

Presentation: oral