TACKLING THE SCOURGE OF WEEDS: THE USE AND CHALLENGE OF HERBICIDES (WEEDKILLERS)

Abstract

The impact of the presence of weeds on crop production is very considerable. Estimates suggest that weeds are responsible for an overall reduction of somewhat more than 10% in the yield of the major world crops, accounting for a huge annual loss of food supplies. Weeds deprive the crop of water, mineral nutrients and light, and so prevent it from achieving full potential (Das, 2011). While in developed countries weed management is done through the use of herbicides and machinery, in poorly developed or developing countries, particularly at the small farm level, the farmer and his/her family spend more than 40 percent of their labour time in handweeding operations. This situation limits the productivity of the farmers and the socio-economic development of their family (FAO, undated). To minimize the direct impact of weeds on crops and achieve optimum crop yield requires the most efficient methods of management.