Influence of Grain Moisture Content on the Efficacy of Silica Dust

Post harvest losses of maize are substantial particularly in developing countries mainly due to insect pests among which the invasive Prostephanus truncatus, also known as the larger grain borer is the most destructive with losses between 9 to 35% or even higher. The larger grain borer was accidentally introduced into East and West Africa in the late 1970s and early 1980s, respectively. Currently, the pest is recorded in 18 sub-Saharan African countries.Grave consequences of losses to the farmer, economies of sub-Saharan Africa and food security are real with recorded annual loss of cereals within the region to the tune of US$ 4 billion. Intervention measures to reduce these post losses are therefore a necessity. Until recently, reliance on chemical pesticides has been fashionable due to quick observable results, but the trend is rapidly changing as environmental concern become important. In response to this, silica dust a more environmental friendly product was investigated as an alternative control product to a mixed population of the larger grain borer and maize weevil. The outcome showed possible use of silica dust on these pests to reduce losses on stored maize.