Reaction of some weed species to herbicides in sugar beet cultivation

In the years 1975-1980, on the Experimental Farm Chylice fields of the Warsaw Agricultural University, herbicide activity was evaluated on commonly appearing weed species in sugar beet cultivation. The most frequent weeds were: Chenopodium album, Echinochloa crus-galli, Polygonum convolvulus and Polygonum lapatifolium . Preemergence use of chloridazon and furthermore postemergence use of phenmedipham were most effective in control. Metolachlor or bentiocarb mixed with metamitron and chloridazon were effective too. It was found that 70% control of Chenopodium album increased crops of sugar beets by about 25% on the basis of two years experiments (1979-1980), differing in quantity and periods of rainfall, a visible dependence of herbicide effectiveness on climatic conditions was demonstrated.