In storage, maize grains are severely destroyed by insects and other storage pests. One of the pr... more In storage, maize grains are severely destroyed by insects and other storage pests. One of the primary causes of grain loss in stored maize is the damage caused by maize weevil, Sitophilus zeamais. A study was conducted to evaluate selected locally available botanical powders and cooking oils for their effectiveness as grain protectants against maize weevils at JUCAVM in year 2011. The plant powders and cooking oils were compared with untreated control and Malathion super dust as standard check. The experiment was laid-out in Completely Randomized Design with 13 treatments each replicated thrice. Different dependent variables such as cumulative adult mortality, F 1 progeny emergency, grain damage were assessed. The results revealed that, among the botanical powders, there was an increased cumulative adult S. zeamais mortality, i.e. higher mortality, from powders of Chenopodium ambrosoides (70% with LT 50 of 6.50 days), Azadiricta indica leaf (70% with LT 50 of 6.00 days), A. indica bark (70% with LT 50 of 8.40 days) and Tagetus erecta (70% with LT 50 of 9.20 days) after 20 days of exposure periods. Apart from the untreated control, low mortality of S. zeamais adult was recorded from Allium sativum (50% with LT 50 of 18.01 days), C. citratus (55% with LT 50 of 18.30 days), Maesa lanceolata (55% with LT 50 of 16.20 days) and Echinops kebericho (55% with LT 50 of 14.50 days) after 20 days of exposure periods. Highest S. zeamais adult mortality of 95%, 100% and 100% was recorded from Brassica carinata oil, Gossypium hirsutum oil and the standard chemical Malathion, respectively with LT 50 of less than one day in all cases. Maximum number of progeny was emerged from untreated check from 25 th~4 0 th days of exposures with cumulative increase (2 to 14 adults). There was no F 1 progeny emergency from the three treatments (oils and Malathion) over the exposure periods reassuring the potency of the cooking oils against S. zeamais. As a result there was no perforated seed; no weight loss and maximum germination percentage of 94.60% were registered from the two cooking oils on par with the Malathion (95.50%). In conclusion, the two cooking oils were found to be the most potent bio-insecticides on par with standard check, Malathion and they can be used in integrated management of maize weevil, S. zeamais.
Maize is the second most widely grown cereal crop in Ethiopia. In storage, maize is severely dest... more Maize is the second most widely grown cereal crop in Ethiopia. In storage, maize is severely destroyed by storage insect pests, mainly maize weevil (Sitophilus zeamais). In an effort to develop a nonsynthetic pesticide control approach, a study was conducted to determine the efficacy of two cooking oils, Ethiopian mustard (Brassica carinata) and cotton (Gossypium hirsutum), to control S. zeamais under laboratory conditions. The oils were applied at the rate of 0.2 to 0.5 ml per 250 g of grain and compared with untreated control and malathion super dust as standard check. The study was laid-out in completely randomized design (CRD) with three replications for each treatment. The efficacy of the oils was assessed on the basis of total insect mortality, median lethal time (LT 50 ), weevil progeny emergence, seed hole's number, weight loss and germination rate. The results showed that the oils caused 25 to 100% mortality at the different concentrations used. Both oils had LT 50 of 0.5 day when applied at the concentration of 0.5 ml. At concentration of 0.3 to 0.5 ml, both oils caused zero weevil progeny emergence, minimum seed damage, zero grain weight loss and 89.2 to 95.5% seed germination rate which were similar to those of malathion (Diethyl succinate) and significantly different from those of the untreated control. The tests demonstrated that the two oils are effective stored maize grain protectants and can be used as components of maize weevil integrated pest management option.
Sitotroga cereallela O. A study was conducted to evaluate selected locally available botanical po... more Sitotroga cereallela O. A study was conducted to evaluate selected locally available botanical powders and two cooking oils for their effectiveness as grain protectants against S. cereallela at Jimma University College of Agriculture and Veterinary Medicine in 2011. The plant powders and cooking oils were compared with untreated control and Malathion super dust as standard control. The experiment was laid-out in completely randomized design with three replications for each treatment. Different dependent variables such as adult mortality, F 1 progeny emergency and grain damage were assessed. The results revealed that there was an increase in adult mortality, decrease in F 1 progeny emergency and grain damage as a result of botanical powders and cooking oils application to maize grains. Among the botanicals, very low mortality of 27.80% was recorded from Maesa lanceolata (with LT 50 of 219.8 days) and Echinops kebericho (with LT 50 of 338.10 days) similar to the untreated control. Cumulative mortality of 39.00% was registered from Azadirachta indica bark powder (with LT 50 of 30.40 days) and Cympopogon citratus leaf (with LT 50 of 171 days) against Sitotroga cerealella 20 days after insect exposure to the botanicals. Maximum moths mortality, 94.4%, was recorded from standard control (Malathion) followed by the two cooking oils (77.8%). No F 1 progeny emerged from the grains treated with the two cooking oils similar to the standard chemical over the exposure period of 40 days leading to no seed with hole, minimum weight loss and maximum seed germination percentage (97.30%). Thus, the two cooking oils were found to be most potent bio-insecticides against maize grain moth on par with standard check, Malathion.
In storage, maize grains are severely destroyed by insects and other storage pests. One of the pr... more In storage, maize grains are severely destroyed by insects and other storage pests. One of the primary causes of grain loss in stored maize is the damage caused by maize weevil, Sitophilus zeamais. A study was conducted to evaluate selected locally available botanical powders and cooking oils for their effectiveness as grain protectants against maize weevils at JUCAVM in year 2011. The plant powders and cooking oils were compared with untreated control and Malathion super dust as standard check. The experiment was laid-out in Completely Randomized Design with 13 treatments each replicated thrice. Different dependent variables such as cumulative adult mortality, F 1 progeny emergency, grain damage were assessed. The results revealed that, among the botanical powders, there was an increased cumulative adult S. zeamais mortality, i.e. higher mortality, from powders of Chenopodium ambrosoides (70% with LT 50 of 6.50 days), Azadiricta indica leaf (70% with LT 50 of 6.00 days), A. indica bark (70% with LT 50 of 8.40 days) and Tagetus erecta (70% with LT 50 of 9.20 days) after 20 days of exposure periods. Apart from the untreated control, low mortality of S. zeamais adult was recorded from Allium sativum (50% with LT 50 of 18.01 days), C. citratus (55% with LT 50 of 18.30 days), Maesa lanceolata (55% with LT 50 of 16.20 days) and Echinops kebericho (55% with LT 50 of 14.50 days) after 20 days of exposure periods. Highest S. zeamais adult mortality of 95%, 100% and 100% was recorded from Brassica carinata oil, Gossypium hirsutum oil and the standard chemical Malathion, respectively with LT 50 of less than one day in all cases. Maximum number of progeny was emerged from untreated check from 25 th~4 0 th days of exposures with cumulative increase (2 to 14 adults). There was no F 1 progeny emergency from the three treatments (oils and Malathion) over the exposure periods reassuring the potency of the cooking oils against S. zeamais. As a result there was no perforated seed; no weight loss and maximum germination percentage of 94.60% were registered from the two cooking oils on par with the Malathion (95.50%). In conclusion, the two cooking oils were found to be the most potent bio-insecticides on par with standard check, Malathion and they can be used in integrated management of maize weevil, S. zeamais.
Maize is the second most widely grown cereal crop in Ethiopia. In storage, maize is severely dest... more Maize is the second most widely grown cereal crop in Ethiopia. In storage, maize is severely destroyed by storage insect pests, mainly maize weevil (Sitophilus zeamais). In an effort to develop a nonsynthetic pesticide control approach, a study was conducted to determine the efficacy of two cooking oils, Ethiopian mustard (Brassica carinata) and cotton (Gossypium hirsutum), to control S. zeamais under laboratory conditions. The oils were applied at the rate of 0.2 to 0.5 ml per 250 g of grain and compared with untreated control and malathion super dust as standard check. The study was laid-out in completely randomized design (CRD) with three replications for each treatment. The efficacy of the oils was assessed on the basis of total insect mortality, median lethal time (LT 50 ), weevil progeny emergence, seed hole's number, weight loss and germination rate. The results showed that the oils caused 25 to 100% mortality at the different concentrations used. Both oils had LT 50 of 0.5 day when applied at the concentration of 0.5 ml. At concentration of 0.3 to 0.5 ml, both oils caused zero weevil progeny emergence, minimum seed damage, zero grain weight loss and 89.2 to 95.5% seed germination rate which were similar to those of malathion (Diethyl succinate) and significantly different from those of the untreated control. The tests demonstrated that the two oils are effective stored maize grain protectants and can be used as components of maize weevil integrated pest management option.
Sitotroga cereallela O. A study was conducted to evaluate selected locally available botanical po... more Sitotroga cereallela O. A study was conducted to evaluate selected locally available botanical powders and two cooking oils for their effectiveness as grain protectants against S. cereallela at Jimma University College of Agriculture and Veterinary Medicine in 2011. The plant powders and cooking oils were compared with untreated control and Malathion super dust as standard control. The experiment was laid-out in completely randomized design with three replications for each treatment. Different dependent variables such as adult mortality, F 1 progeny emergency and grain damage were assessed. The results revealed that there was an increase in adult mortality, decrease in F 1 progeny emergency and grain damage as a result of botanical powders and cooking oils application to maize grains. Among the botanicals, very low mortality of 27.80% was recorded from Maesa lanceolata (with LT 50 of 219.8 days) and Echinops kebericho (with LT 50 of 338.10 days) similar to the untreated control. Cumulative mortality of 39.00% was registered from Azadirachta indica bark powder (with LT 50 of 30.40 days) and Cympopogon citratus leaf (with LT 50 of 171 days) against Sitotroga cerealella 20 days after insect exposure to the botanicals. Maximum moths mortality, 94.4%, was recorded from standard control (Malathion) followed by the two cooking oils (77.8%). No F 1 progeny emerged from the grains treated with the two cooking oils similar to the standard chemical over the exposure period of 40 days leading to no seed with hole, minimum weight loss and maximum seed germination percentage (97.30%). Thus, the two cooking oils were found to be most potent bio-insecticides against maize grain moth on par with standard check, Malathion.
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