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

Abstract

Field and laboratory experiments were conducted at Bako Research Center, Western Ethiopia, during 2010/11-2011/12 to evaluate farmers’ traditional practices (layering of tef over sorghum with 20% proportion, mixing sorghum with tef at 30% w/w, mixing sorghum with partially grinded hot pepper at the rate of 2% w/w and 1% w/w) in comparison with Malathion 5% D and untreated check against insect pest of stored sorghum. Similarly, in a laboratory study combinations of different rates of Malathion 5% D (100, 50, 40, 30, 20, 10, 0%) and Neem seed powder (10, 20, 30, 40, 50%) were evaluated against maize weevils from February to - July 2012. Results of the study showed that the number and weight of damaged grains were 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 were significantly (p<0.05) lower in mixing sorghum with hot pepper at 2% and 1% w/w than the other treatments, when compared to standard check. Among treatments, mortality in all of the treatment combinations ranged from 3.33 to-100%, while that of the untreated check ranged from 0 to-5.33% following 90 days after infestation. Similarly, the number of progeny weevils emerged, percentages of grain damaged and seed weight losses in all 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 were observed for damaged grains and seed weight losses 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 could be concluded that mixing sorghum with partially grinded chillies (hot pepper) at the rate of 2% w/w or 1% w/w can be used to protect stored sorghum from insect pests and the combinations of Malathion 5% D and Neem seed powder at 40%+20% and 50%+10% respectively, can be used to protect maize from the maize weevil.