Chemical weed control in the winter wheat (Triticum aestivum L.) crop of early stages of development: II. Crop productivity

Abstract

Field trials were carried out at the Jonas Aliukonis farm in Prienai district, Strielciu village, during 2005-2006. Influence of 5 herbicides applied in autumn on crop of winter wheat was investigated. Hypothesis was that applying herbicides in autumn will control weeds that survive during winter time and it will lead to increase of the winter wheat {Triticum aestivum L.) grain yield. The aim of this work was to evaluate influence of various herbicide applications in autumn at early stages of development of winter wheat crop on grain yield productivity. Herbicide application in autumn at early stages of winter wheat development significantly decreased crop weediness as well in spring vegetation after over-wintering. The reliable linear dependence was established between weed air-dry biomass left in the crop after spraying autumn herbicides and weed air-dry biomass before conventional spraying with herbicides in spring (r = 0.608"). Winter wheat grain yield dependence on crop weediness (weed number and biomass) was described by reverse linear correlation (r = -0.565" and r = -0.438" accordingly). The statistically significant increase of the winter wheat grain yield by 0.62-0.S7 t ha'1 was established after use of Monitor, Mustang, Logran and Husar comparing with non-treated control plots in autumn vegetation; winter wheat grain yield increased till 25.0%, 20.1 %, 18.8% and 23.6%, accordingly. After spraying with Atribut winter wheat grain yield had just a tendency to increase.