Background:Anoplophora glabripennis(Motschulsky),commonly known as Asian longhorned beetle(ALB),is a wood-boring insect that can cause lethal infestation to multiple borer leaf trees.In Gansu Province,northwest China,...Background:Anoplophora glabripennis(Motschulsky),commonly known as Asian longhorned beetle(ALB),is a wood-boring insect that can cause lethal infestation to multiple borer leaf trees.In Gansu Province,northwest China,ALB has caused a large number of deaths of a local tree species Populus gansuensis.The damaged area belongs to Gobi desert where every single tree is artificially planted and is extremely difficult to cultivate.Therefore,the monitoring of the ALB infestation at the individual tree level in the landscape is necessary.Moreover,the determination of an abnormal phenotype that can be obtained directly from remote-sensing images to predict the damage degree can greatly reduce the cost of field investigation and management.Methods:Multispectral WorldView-2(WV-2)images and 5 tree physiological factors were collected as experimental materials.One-way ANOVA of the tree’s physiological factors helped in determining the phenotype to predict damage degrees.The original bands of WV-2 and derived vegetation indices were used as reference data to construct the dataset of a prediction model.Variance inflation factor and stepwise regression analyses were used to eliminate collinearity and redundancy.Finally,three machine learning algorithms,i.e.,Random Forest(RF),Support Vector Machine(SVM),Classification And Regression Tree(CART),were applied and compared to find the best classifier for predicting the damage stage of individual P.gansuensis.Results:The confusion matrix of RF achieved the highest overall classification accuracy(86.2%)and the highest Kappa index value(0.804),indicating the potential of using WV-2 imaging to accurately detect damage stages of individual trees.In addition,the canopy color was found to be positively correlated with P.gansuensis’damage stages.Conclusions:A novel method was developed by combining WV-2 and tree physiological index for semi-automatic classification of three damage stages of P.gansuensis infested with ALB.The canopy color was determined as an abnormal phenotype that could be directly assessed using remote-sensing images at the tree level to predict the damage degree.These tools are highly applicable for driving quick and effective measures to reduce damage to pure poplar forests in Gansu Province,China.展开更多
Activities of carboxylesterase and glutathione S transferase in Anoplophora glabripennis larvae feeding on eight different kinds of poplar trees were tested. The results showed that the activities of the two enzymes w...Activities of carboxylesterase and glutathione S transferase in Anoplophora glabripennis larvae feeding on eight different kinds of poplar trees were tested. The results showed that the activities of the two enzymes were significantly different when the larvae feeding on different poplar trees. The contents of fourteen secondary metabolites in eight kinds of poplar trees were also tested with the method of high pressure liquid chromatography (HPLC). Stepwise regression analysis was carried out to test the relationship between the activities of the enzymes and secondary metabolites of poplar trees. The analysis results demonstrated that the contents of benzoic acid and catechin decreased together with the increase of carboxylesterase activity while the contents of catechol increased, but the content of p hydroxybenzoic acid decreased together with the increasing of glutathione S transferase activity while the content of phenol, coumaric acid, syringic, salicylic acid and salicin in poplar trees increased.展开更多
Data from a survey in the Hasi Mountain areas of Jinyuan County in Gansu province of China showed that 83.3% white birch(Betula platyphylla) stand was infested by the Asian longhorned beete,Anoplophroa glabripennis.Th...Data from a survey in the Hasi Mountain areas of Jinyuan County in Gansu province of China showed that 83.3% white birch(Betula platyphylla) stand was infested by the Asian longhorned beete,Anoplophroa glabripennis.The longevity of the beetles was(41.2±11.5) days for a male and(39.1±13.1) days for a female when twigs of white birch were used as a sole source of food for the adult beetles.The area of twig barks consumed by a pair of beetles in their life time was(9.93±8.15) cm2.A female can make(12.4±12.1) egg pits in average during the period when they were alive and caged.If removal of the infested tree is used as a management measure,it must be excuted consecutively for two years to be effective.Field tests were conducted in 2005 and 2006 to treat infested trees with imidacloprid through trunk injection,soil injection,and soil drench.The results showed that the number of dead adults under the treated trees was 6.3 times for trunk injection,5.1 times for soil injection,and 4.9 times for soil drench more than that under the untreated control.The number of live larvae decreased by 95.8% for trunk injection,83.3% for soil injection,and 85.5% for soil drench in comparison with larva mortality in control.The number of egg pits made on tree trunks by an adult was decreased by 87.1%、77.4%and 82.6%for imidacloprid trough trunk injection,soil injection,and soil drench,respectively,compared with the untreated control.展开更多
基金supported by National Key Research&Development Program of China“Research on key technologies for prevention and control of major disasters in plantation”(Grant No.2018YFD0600200)Beijing’s Science and Technology Planning Project“Key technologies for prevention and control of major pests in Beijing ecological public welfare forests”(Grant Nos.Z191100008519004 and Z201100008020001).
文摘Background:Anoplophora glabripennis(Motschulsky),commonly known as Asian longhorned beetle(ALB),is a wood-boring insect that can cause lethal infestation to multiple borer leaf trees.In Gansu Province,northwest China,ALB has caused a large number of deaths of a local tree species Populus gansuensis.The damaged area belongs to Gobi desert where every single tree is artificially planted and is extremely difficult to cultivate.Therefore,the monitoring of the ALB infestation at the individual tree level in the landscape is necessary.Moreover,the determination of an abnormal phenotype that can be obtained directly from remote-sensing images to predict the damage degree can greatly reduce the cost of field investigation and management.Methods:Multispectral WorldView-2(WV-2)images and 5 tree physiological factors were collected as experimental materials.One-way ANOVA of the tree’s physiological factors helped in determining the phenotype to predict damage degrees.The original bands of WV-2 and derived vegetation indices were used as reference data to construct the dataset of a prediction model.Variance inflation factor and stepwise regression analyses were used to eliminate collinearity and redundancy.Finally,three machine learning algorithms,i.e.,Random Forest(RF),Support Vector Machine(SVM),Classification And Regression Tree(CART),were applied and compared to find the best classifier for predicting the damage stage of individual P.gansuensis.Results:The confusion matrix of RF achieved the highest overall classification accuracy(86.2%)and the highest Kappa index value(0.804),indicating the potential of using WV-2 imaging to accurately detect damage stages of individual trees.In addition,the canopy color was found to be positively correlated with P.gansuensis’damage stages.Conclusions:A novel method was developed by combining WV-2 and tree physiological index for semi-automatic classification of three damage stages of P.gansuensis infested with ALB.The canopy color was determined as an abnormal phenotype that could be directly assessed using remote-sensing images at the tree level to predict the damage degree.These tools are highly applicable for driving quick and effective measures to reduce damage to pure poplar forests in Gansu Province,China.
文摘Activities of carboxylesterase and glutathione S transferase in Anoplophora glabripennis larvae feeding on eight different kinds of poplar trees were tested. The results showed that the activities of the two enzymes were significantly different when the larvae feeding on different poplar trees. The contents of fourteen secondary metabolites in eight kinds of poplar trees were also tested with the method of high pressure liquid chromatography (HPLC). Stepwise regression analysis was carried out to test the relationship between the activities of the enzymes and secondary metabolites of poplar trees. The analysis results demonstrated that the contents of benzoic acid and catechin decreased together with the increase of carboxylesterase activity while the contents of catechol increased, but the content of p hydroxybenzoic acid decreased together with the increasing of glutathione S transferase activity while the content of phenol, coumaric acid, syringic, salicylic acid and salicin in poplar trees increased.
文摘Data from a survey in the Hasi Mountain areas of Jinyuan County in Gansu province of China showed that 83.3% white birch(Betula platyphylla) stand was infested by the Asian longhorned beete,Anoplophroa glabripennis.The longevity of the beetles was(41.2±11.5) days for a male and(39.1±13.1) days for a female when twigs of white birch were used as a sole source of food for the adult beetles.The area of twig barks consumed by a pair of beetles in their life time was(9.93±8.15) cm2.A female can make(12.4±12.1) egg pits in average during the period when they were alive and caged.If removal of the infested tree is used as a management measure,it must be excuted consecutively for two years to be effective.Field tests were conducted in 2005 and 2006 to treat infested trees with imidacloprid through trunk injection,soil injection,and soil drench.The results showed that the number of dead adults under the treated trees was 6.3 times for trunk injection,5.1 times for soil injection,and 4.9 times for soil drench more than that under the untreated control.The number of live larvae decreased by 95.8% for trunk injection,83.3% for soil injection,and 85.5% for soil drench in comparison with larva mortality in control.The number of egg pits made on tree trunks by an adult was decreased by 87.1%、77.4%and 82.6%for imidacloprid trough trunk injection,soil injection,and soil drench,respectively,compared with the untreated control.
