Biology, occurrence and control of weeds in crops

Weeds currently represent a constant risk to the crop plants. They are able to either suppress the development of a crop plant in the initial period of its growth or to hinder and even make the harvest impossible due to its stand density at the end of the vegetative phase before the harvest. Perennial weeds rank among very noxious weeds. They are highly resistant and able to adapt to the used control measures. The character of the crop plants itself and the applied agronomic practices determine the occurrence of different weed species. For this reason, the question of how to deal with weeds still remains crucial. The diploma thesis is focused on the occurrence and the harmful effects of selected weeds in two Maize hybrids (Zea mays). The incidence of weeds and the effect of herbicides on those weeds were monitored within an experiment conducted on a small plot of land. The following weed plants occurred: Couch-grass (Elytrigia repens L.), Creeping thistle (Cirsium arvense L.), Barnyard grass (Echinochloa crus-galli L.), Scentless mayweed (Tripleurospermum inodorum L.), Goosegrass (Galium aparine L.) etc. The aim of the thesis is to expand knowledge of the use of different weed control methods in Maize. Recommendations on the use of those methods in agriculture shall be suggested