Efficacy of Herbicides, Herbicide Tank Mixtures and Herbicide Combinations on Express Sun Oil-Bearing Sunflower (Helianthus Annuus L.)

Abstract

During the period 2018-2020 a field experiment has been carried out with the oil-bearing sunflower hybrid P64LЕ121 (Helianthus annuus L.). It is a sulfo tolerant hybrid by ExpressSun technology. A total of 25 variants were investigated. They included untreated control, 2 herbicides applied alone in addition with adjuvant Trend 90, 10 herbicide tank mixtures and 10 herbicide combinations. Soil-applied combined herbicides were performed during after sowing before emergence period of the sunflower. Foliar-applied herbicides were performed during 3-4 leaf sunflower stage. Full control of annual broadleaved weeds in ExpressSun oil-bearing is provided by a single treatment with herbicide Fluence at a dose of 40 g/ha or with herbicide Evorelle express at a dose of 60 g/ha applied during 3-4 leaf sunflower stage. Full controls of perennial broadleaved weeds is provided by two treatments with herbicide Fluence in doses of 20+20 g/ha or with herbicide Evorelle express in doses of 30+30 g/ha, applied during 3-4 leaf and 7-8 leaf sunflower stages. In the presence of annual and perennial broadleaved and graminaceous weeds, it is necessary to apply Fluence and Evorelle express as herbicide tank mixtures together with foliar-applied antigraminaceous herbicides Fusilade forte, Stratos ultra or Targa max. In the absence of perennial graminaceous weeds, it is necessary to apply herbicides Fluence and Evorelle express as herbicide combinations with soil-applied antigraminaceous herbicides Dual gold or Indipen. The highest seed yield is obtained by herbicide tank mixture Fluence + Fusilade forte, followed by herbicide tank mixture Evorelle express + Stratos ultra. High seed yields are also obtained by use of herbicide combinations Indipen + Evorelle express and Dual gold + Fluence.