The aim of this study is to evaluate the insecticidal potential of aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae on Caryedon serratus Ol.(Coleoptera,Bruchidae),an insect pest of groundnut...The aim of this study is to evaluate the insecticidal potential of aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae on Caryedon serratus Ol.(Coleoptera,Bruchidae),an insect pest of groundnut grains in the Republic of Guinea.To do this,tests on their insecticidal efficacy were carried out separately on groups of 8 bruchids using concentrations of aqueous extracts from their leaves in jars each containing 20 g of groundnut.The mortality of the bruchids and the impact of their aqueous extracts were observed and recorded for 96 h and 120 days after infestation,followed by a test of the germinative power of the seeds.Concentrations(C1)of aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae applied to 20 g of groundnut resulted in bruchid mortality of 86.99%and 78.82%of each plant respectively.At the same doses,the treated seeds were not attacked during 4 months’storage.The germination rate of groundnut seeds at the start and end of the experiment was 97.65%and 93.60%respectively.Thus,aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae can be considered as an alternative bio-insecticide against pests in groundnut storage shops.展开更多
Ethanolic extracts of five plant material from Eucalyptus gluaca, Melia azadrach, Mentha arvensis, Olea europaea leaves and periearp of Punica granatum were investigated for insecticidal activity against the confused ...Ethanolic extracts of five plant material from Eucalyptus gluaca, Melia azadrach, Mentha arvensis, Olea europaea leaves and periearp of Punica granatum were investigated for insecticidal activity against the confused flour beetle Tribolium confusum DuVal in the laboratory. Different concentrations 2.5%, 5%, 7.5%, 10% using filter paper test were implemented in the experiment. Mortality was assessed after 24, 48, 72 hrs of treatment and LDs0 were calculated at respective time intervals. Data analysis was made by using factorial Complete Randomized Design （CRD）. The results revealed that all of the tested materials with some variations had lethal effects against the pest as compared with the untreated check. The time 24 h showed higher insecticidal effect with the tested concentrations for the larvae and adult of Tribolium confusum. Strong toxicity effect was observed at concentration 5% of M.. arvensis for adult followed by E. gluaca, O. europaea, M.. azedrach and P. granatum. For larval stage the extract of O. europaea and E. gluaca with concentration 7.5%, 1%, respectively caused high mortality followed by M. arvensis, M. azedrach and P. granatum. The LDs0 values for adults and larvae were calculated to be 1.33 and 1.42 with M.. arvensis and O. europaea, respectively.展开更多
The utilization of natural materials in the post-harvest process of agricultural products is necessary for the production of safe food.In recent years,the use of essential oil extracted from aromatic plants has shown ...The utilization of natural materials in the post-harvest process of agricultural products is necessary for the production of safe food.In recent years,the use of essential oil extracted from aromatic plants has shown significant potential for insect pest management.Toxicity and antifeedant effects of essential oil isolated from aerial parts of Teucrium polium L.have been investigated against the red flour beetle,Tribolium castaneum Herbst,as one of the most detrimental insect pests of post-harvest cereals in the present study.The chemical profile of this oil was also assessed by gas chromatography-mass spectrometry(GC-MS)and lycopersene(26.00%),dodecane(14.78%),1,5-dimethyl decahydronaphthalene(9.27%)and undecane(7.18%)were identified as main components.For evaluation of the fumigant toxicity and antifeedant effects using multiple regression analysis,a quadratic polynomial and linear equation were obtained,respectively.Adequacy and accuracy of the fitted models were checked through analysis of variance.T.polium essential oil exhibited significant fumigant toxicity on the T.castaneum adults and based on modeling using RSM,the concentration of 20μl/l and 72 min exposure time was calculated as the optimum conditions for 97.97%mortality with 87.8%desirability.A concentration of 14.13μl/l was also estimated as the optimum value for 94.66%Feeding Deferens Index with 92%desirability.The mortality and anti-nutritional effect,in general,increased with increasing of exposure times and the essential oil concentrations.Results designated a great potential of T.polium essential oil for management of the red flour beetle.Further,it was found that the Response Surface Methodology was a promising method for the prediction of these bio-effects.展开更多
Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none o...Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in S. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract＋3 ml methanol and 1 g extract＋5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract＋l 5 ml methanol had no significant lethal effect on Sitophilus zeamais.展开更多
文摘The aim of this study is to evaluate the insecticidal potential of aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae on Caryedon serratus Ol.(Coleoptera,Bruchidae),an insect pest of groundnut grains in the Republic of Guinea.To do this,tests on their insecticidal efficacy were carried out separately on groups of 8 bruchids using concentrations of aqueous extracts from their leaves in jars each containing 20 g of groundnut.The mortality of the bruchids and the impact of their aqueous extracts were observed and recorded for 96 h and 120 days after infestation,followed by a test of the germinative power of the seeds.Concentrations(C1)of aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae applied to 20 g of groundnut resulted in bruchid mortality of 86.99%and 78.82%of each plant respectively.At the same doses,the treated seeds were not attacked during 4 months’storage.The germination rate of groundnut seeds at the start and end of the experiment was 97.65%and 93.60%respectively.Thus,aqueous extracts of the leaves of Erythrophleum guineense and Uvaria chamae can be considered as an alternative bio-insecticide against pests in groundnut storage shops.
文摘Ethanolic extracts of five plant material from Eucalyptus gluaca, Melia azadrach, Mentha arvensis, Olea europaea leaves and periearp of Punica granatum were investigated for insecticidal activity against the confused flour beetle Tribolium confusum DuVal in the laboratory. Different concentrations 2.5%, 5%, 7.5%, 10% using filter paper test were implemented in the experiment. Mortality was assessed after 24, 48, 72 hrs of treatment and LDs0 were calculated at respective time intervals. Data analysis was made by using factorial Complete Randomized Design （CRD）. The results revealed that all of the tested materials with some variations had lethal effects against the pest as compared with the untreated check. The time 24 h showed higher insecticidal effect with the tested concentrations for the larvae and adult of Tribolium confusum. Strong toxicity effect was observed at concentration 5% of M.. arvensis for adult followed by E. gluaca, O. europaea, M.. azedrach and P. granatum. For larval stage the extract of O. europaea and E. gluaca with concentration 7.5%, 1%, respectively caused high mortality followed by M. arvensis, M. azedrach and P. granatum. The LDs0 values for adults and larvae were calculated to be 1.33 and 1.42 with M.. arvensis and O. europaea, respectively.
文摘The utilization of natural materials in the post-harvest process of agricultural products is necessary for the production of safe food.In recent years,the use of essential oil extracted from aromatic plants has shown significant potential for insect pest management.Toxicity and antifeedant effects of essential oil isolated from aerial parts of Teucrium polium L.have been investigated against the red flour beetle,Tribolium castaneum Herbst,as one of the most detrimental insect pests of post-harvest cereals in the present study.The chemical profile of this oil was also assessed by gas chromatography-mass spectrometry(GC-MS)and lycopersene(26.00%),dodecane(14.78%),1,5-dimethyl decahydronaphthalene(9.27%)and undecane(7.18%)were identified as main components.For evaluation of the fumigant toxicity and antifeedant effects using multiple regression analysis,a quadratic polynomial and linear equation were obtained,respectively.Adequacy and accuracy of the fitted models were checked through analysis of variance.T.polium essential oil exhibited significant fumigant toxicity on the T.castaneum adults and based on modeling using RSM,the concentration of 20μl/l and 72 min exposure time was calculated as the optimum conditions for 97.97%mortality with 87.8%desirability.A concentration of 14.13μl/l was also estimated as the optimum value for 94.66%Feeding Deferens Index with 92%desirability.The mortality and anti-nutritional effect,in general,increased with increasing of exposure times and the essential oil concentrations.Results designated a great potential of T.polium essential oil for management of the red flour beetle.Further,it was found that the Response Surface Methodology was a promising method for the prediction of these bio-effects.
文摘Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in S. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract＋3 ml methanol and 1 g extract＋5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract＋l 5 ml methanol had no significant lethal effect on Sitophilus zeamais.
