The migratory locust Locusta migratoria(Orthoptera,Acrididae)is one of the most important pests due to its extensive and severe damage to crops in large parts of Africa and Asia.Biodegradable and ecologically natural ...The migratory locust Locusta migratoria(Orthoptera,Acrididae)is one of the most important pests due to its extensive and severe damage to crops in large parts of Africa and Asia.Biodegradable and ecologically natural products such as bota nical insecticides are emergi ng can didates for replaceme nt of usually applied chemical pesticides.The crude methanolic extract of Pergularia tomentosa(PME)was investigated for their toxicity and physiological aspects on L.migratoria nymphs.Results showed that treatment of newly emerged fourth and fifth instar nymphs resulted in significant mortality and significant repellent activity with an LC50 value of 0.18 and 0.38%,respectively,after seven days of treatment.The PME toxicity was also dem on strated by histopathological cha nges in the alime ntary canal resulting in con siderable disorganization and severe damage of the caeca and proventriculus structure.The extract induced cellular immune reactions which manifested by a significant decrease in the number of the differential haemocyte counts(prohemocytes and plasmatocytes)and important cell lysis.Data of biochemical analyses showed that the PME reduced the activity of acetylcholinesterase and induced the glutathione S-transferases.The neurotoxic effect was confirmed by the histological alterations in the brain structure,particularly in the neurosecretory cells showing typical signs of cell necrosis.展开更多
Attract and kill （AK） technology was evaluated against the Mediterranean fruit fly （Med-fly）, Ceratitis capitata W.. Treatment was carried out in two peach orchards of four hectares each; first one located in Borj...Attract and kill （AK） technology was evaluated against the Mediterranean fruit fly （Med-fly）, Ceratitis capitata W.. Treatment was carried out in two peach orchards of four hectares each; first one located in Borj-Touil and the second in El-Kssibi Mornag, Northern Tunisia during the 2012 field season. AK is a specialized system based on hydrolyzed proteins and alpha-cypermethrin. During this study, 400 AK bait stations were placed in every hectare, four weeks before fruits color changes. The tested AK system was found effective in reducing the number of C. capitata population to 70% comparing to the untreated orchards. Fruit damages assessment showed significant differences between treatments in respect of decreasing infestation onto fruits Study results indicated that AK baited treatments were able to reduce dropped and soften fruits infestation seven times than that of control plots. Fruit damages were restricted to 4%-5% in treated areas with AK system in compare to 31%-35% recorded in control plots. This novel AK system showed good performance to combat Med-fly and can successfully used to combat various fruit fly species when applied for an area wide application program.展开更多
文摘The migratory locust Locusta migratoria(Orthoptera,Acrididae)is one of the most important pests due to its extensive and severe damage to crops in large parts of Africa and Asia.Biodegradable and ecologically natural products such as bota nical insecticides are emergi ng can didates for replaceme nt of usually applied chemical pesticides.The crude methanolic extract of Pergularia tomentosa(PME)was investigated for their toxicity and physiological aspects on L.migratoria nymphs.Results showed that treatment of newly emerged fourth and fifth instar nymphs resulted in significant mortality and significant repellent activity with an LC50 value of 0.18 and 0.38%,respectively,after seven days of treatment.The PME toxicity was also dem on strated by histopathological cha nges in the alime ntary canal resulting in con siderable disorganization and severe damage of the caeca and proventriculus structure.The extract induced cellular immune reactions which manifested by a significant decrease in the number of the differential haemocyte counts(prohemocytes and plasmatocytes)and important cell lysis.Data of biochemical analyses showed that the PME reduced the activity of acetylcholinesterase and induced the glutathione S-transferases.The neurotoxic effect was confirmed by the histological alterations in the brain structure,particularly in the neurosecretory cells showing typical signs of cell necrosis.
文摘Attract and kill （AK） technology was evaluated against the Mediterranean fruit fly （Med-fly）, Ceratitis capitata W.. Treatment was carried out in two peach orchards of four hectares each; first one located in Borj-Touil and the second in El-Kssibi Mornag, Northern Tunisia during the 2012 field season. AK is a specialized system based on hydrolyzed proteins and alpha-cypermethrin. During this study, 400 AK bait stations were placed in every hectare, four weeks before fruits color changes. The tested AK system was found effective in reducing the number of C. capitata population to 70% comparing to the untreated orchards. Fruit damages assessment showed significant differences between treatments in respect of decreasing infestation onto fruits Study results indicated that AK baited treatments were able to reduce dropped and soften fruits infestation seven times than that of control plots. Fruit damages were restricted to 4%-5% in treated areas with AK system in compare to 31%-35% recorded in control plots. This novel AK system showed good performance to combat Med-fly and can successfully used to combat various fruit fly species when applied for an area wide application program.
