AGRO–ECOLOGICAL ASPECTS OF THE WEED INFESTATION CONTROL IN BIRDSFOOT TREFOIL GROWN FOR FORAGE

Abstract

Effect of the herbicides Stratos Ultra (1000 and 2000 ml/ha) and Pulsar 40 (1000 and 1200 ml/ha) on the degree of weed infestation and productivity of birds foot trefoil was studied in the experimental field of the IMSA–Troyan during the 2010–2012 period on light grey pseudopodzolic soil. It was found that the herbicide Pulsar 40 applied at the dose of 1200 ml/ha, had high selectivity and was suitable for foliar treatment at the 2–4 leaf stage of birds foot trefoil, its herbicidal efficacy reaching 65, 76 and 98% during the years. The herbicide Stratos Ultra applied at the two doses of 1000 and 2000 ml/ha, was more unstable with regard to the dry mass yield. The produced yields of dry mass varied within a greater range depending on the degree of weed infestation, shown herbicidal effect and meteorological conditions. The yield was influenced to a greater extent by the herbicide type and to a smaller one by the dose of its application.