IMPACT OF HERBICIDAL ACTIVE SUBSTANCES ON WEED CONTROL IN FACULTATIVE WHEAT
Background. In an integrated wheat production, in simplified crop rotation (winter wheat – facultative wheat) effective solutions should be sought based on total and selective herbicides in weed control. Material and methods. In a field experiment carried out in the years 2010–2014, the effect of autumn application of glyphosate was investigated, as well as of various active substances in selective herbicides used in spring on the number and weight of mono- and dicotyledonous weeds in the cultivation of spring wheat cv. Monsun sown as facultative wheat.
Results. The spectrum of weed species occurring over the years of research was determined, as well as herbicidal effectiveness of glyphosate and chosen selective herbicides. The highest reduction in the number of dicotyledonous weeds was observed after spring application of tribenuron-methyl, tifensulfuron-methyl with chlorosulfuron, as well as diflufenican and isoproturon. Reduction in the biomass of dicotyledonous weeds for particular variants was: 96% – Chisel 75 WG, 95% – Helmstar 75 WG, 93% – Legato Plus 600 SC, 78% – Chwastox Extra 300 SL + Apyros 75 WG and 68% Starane Super 101 SE + Apyros 75 WG, respectively. Application of glyphosate in the autumn before sowing facultative wheat contributed to a three-fold reduction in the number of monocotyledonous weeds, and in their biomass in the cultivation of wheat cv. Monsun.
Conclusion. In order to achieve the best result of reducing weeds in the cultivation of spring wheat in late-autumn sowing, after cereal forecrop, glyphosate should be applied to autumn crops, and in the spring a suitable herbicide should be selected for the spectrum of the occurring weeds, which contains at least two active substances, e.g. tifensulfuron-methyl with chlorosulfuron or diflufenican with isoproturon.