Farmers’ Practices and Combinations of Malathion and Neem Seed Powder Management Options on Stored Sorghum and Maize Insect Pests at Bako, West Shoa, Ethiopia

Abstract

Some farmers’ practices (layering of tef over sorghum with 20% proportion, mixing sorghum with tef at 30% w/w, mixing sorghum with partially grindedhot pepper at the rate of 2% w/w and 1% w/w) including Malathion 5% D and untreated check were evaluated against stored sorghum insect pests at Bako Research Center, Western Ethiopia, from 2010/11-2011/12G.C Besides, combinations of different rates of Malathion 5% D and neem seed powder were evaluated against maize weevils in the laboratory at Bako from February-July 2012. Number and weight of damaged grains significantly (p<0.05) higher in layering of tef over sorghum with 20% w/w, mixing sorghum with tef at 30% w/w and untreated check than the other treatments Similarly, percent weight losses significantly (p<0.05) lower in mixing sorghum with hot pepper at 2% and 1% w/w than the other treatments, which was similar to standard check. As to combine treatments, mortality in all of the treatment combinations ranged from 3.33-100% while that of the untreated check ranged from 0-5.33% following 90 days after infestation Similarly, the number of progeny weevils emerged, percentages of grain damaged and seed weight losses in all of the treatment combinations were significantly lower than that of the untreated check 90 days after infestation. Significantly (P<0.05) higher percentages of mortality, lower percentages of damaged grains and seed weight losses were observed in the Malathion dust at 40% and 50% combined with neem seed powder than that of the other treatments next to the standard check 156 days after infestation. From these studies it can be concluded that mixing sorghum with partially grinded hot pepper at the rate of 2% w/w and 1% w/w can be used to protect stored sorghum insect pests and combinations of malathion and neem seed powder at 40%+20% and 50%+10% can be used to protect maize from the maize weevil.