The influence of selected herbicides and their mixtures used with split application method on weed infestation growth and yield of onion

The studies carried out in the years of 2014–2017 at the Institute of Horticulture in Skierniewice were aimed to compare the biological effectiveness of foliar applied herbicides: oxyfluorfen, prosulfocarb, bromoxynil, pyridate and their mixtures, as well as assessment of suitability of these substances for weeds control in sowed onion. Herbicides were applied with the split application method, in three treatments, every 5–8 days from 1‒2 true leaves stage of onion or in two treatments from 2–3 leaves of onion. The studies assessed the effect of herbicides and their mixtures on the degree of weed damage, secondary weed infestation, selectivity, as well as onion growth, development and yield. The results showed that the greatest reduction of weeds and the highest yield, with slight, transient phytotoxicity symptoms, were obtained after 3 times spraying with oxyfluorofen in a mixture with bromoxynil. The weakest weed control and the lowest onion yield were obtained after applying oxyfluorfen in two treatments, in a mixture with pyridate.