| Pyrrhalta aenescens(Fairmaire)is the main pest in urban gardens.In this study,we studied the living habits,the spatial distribution of overwintering adults and the feeding choice of hosts,and we screened the best control methods for different insect states in order to master the occurrence refularity of Pyrrhalta aenescens(Fairmaire),to carry out"precise control".The main findings are as follows:1.Pyrrhalta aenescens(Fairmaire)appeared twice a year in Changchun area,and have the phenomenon of generation overlap,and it overwintered as an adult.Pyrrhalta aenescens(Fairmaire)feeds on leaves in both adult and larval stages,and it can secrete mucus to harm the host in pupal stage.In the laboratory,the hatching rate of eggs was above 84.2%,the emergence rate of adults was 92.3%,and the peak period of adult emergence was in the middle and late August.2.Populus bolleana LaucheThe vertical distribution range of Pyrrhalta aenescens(Fairmaire)overwintering adults was 96.35%within the range of 0-5cm in soil,and the horizontal distribution range was 46.21%within the range of 0-50cm from the base of tree trunk.45.84%of the adults were females and 54.16%were males before overwintering.after overwintering,51.94%of the adults were females and 48.06%were males.After overwintering,the females accounted for 62.94%and the males accounted for 37.06%among the adults who climb the tree.The spatial distribution pattern of overwintering adults of Pyrrhalta aenescens(Fairmaire)in forest belongs to negative binomial distribution,The linear regression equation is as follows:m*=0.08824+1.24780 m(R=0.9955),Its spatial distribution is aggregation distribution,and the aggregation level increases with the increase of population density,the causes of aggregation are related to environmental factors,such as the living habits of the field and forest and the allocation of forest communities,etc.The equation of the optimal theoretical sampling number of Pyrrhalta aenescens(Fairmaire):N=(1.08824/x+0.24780)/D~2。3.Pyrrhalta aenescens(Fairmaire)only feeds on elm leaves,and when the feeding pressure is high,it still only feeds on the host,which has strict specificity.4.In the chemical control of overwintering adults of Pyrrhalta aenescens(Fairmaire),we recommend the application of 1.2%Nicotine emulsifiable concentrate(concentration 600 or1000 times)or 1.5%1 matrine 2 nicotine(concentration 600,1000 or 1200 times).The control effect was 100%.In the chemical control of the larvae of Pyrrhalta aenescens(Fairmaire)pupa collection,we recommend the application of 600 times liquid of 1.5%matrine nicotine、1200,2000 or 3000times liquid of 20%chlorobenzamide、1000 or 3000 times liquid of 2%methylamino abamectin benzoate、1000 or 3000 times liquid of 40%chlorpyrifos,the control effect was 100%. |
