Study On The Dispersal Behavior Of Eucryptorrhynchus Scrobiculatus Motschulsky And E.brandti(harold)adult

Eucryptorrhynchus scrobiculatus and E.brandti are borer pests,which have caused serious losses to the ecology and economy of Ningxia.In the United States,these two speciess are potential biological control agents for controlling Ailanthus altissima.Studying the population spread,population dynamics,and individual movement characteristics of two species are important for guiding the monitoring and control of these two pests,and it may also provide a reference for evaluating its potential value as a biological control agent for A.altissima.Based on field investigations,this paper studies the effects of wind speed and wound on the dispersal ability of E.scrobiculatus through laboratory research,and marks,releases,and recaptures E.scrobiculatus under natural conditions in the field.Using insect harmonic radar to explore the E.scrobiculatus,the effects of electronic tag marking on dispersal and survivability,and research on the trajectory of E.scrobiculatus toward A.altissima was conducted.The main results are as follows:1.There were no significant differences in the capture rates of the attractant and non-attractant plots(Chi-square test: χ~2 = 1.5329,df = 1,p = 0.216)or in the direction that weevils dispersed(east: F= 0.006,df = 1,P = 0.938;west: F = 0.002,df = 1,p = 0.968).Under natural conditions,the maximum dispersal distance of the population within 60 days is 67.5 m,and the average dispersal rate is 1.14 m/d.The equation of dispersal distance as a function of time is y = 44.5844 + 0.8252x–0.0074x~2.E.scrobiculatus spread along with the host.2.Wounding promotes the dispersal of E.scrobiculatus to wounded trees.Wind speed had a significant effect on the dispersal of adult(F = 95.8,df = 2,p < 0.01).The dispersal rate of E.scrobiculatus was higher when the wind speed was 3.1 m/s(5.4±0.3 cm/s)than when the wind speed was 2.4 m/s(3.1±0.3 cm/s)or 1.8 m/s(1.3±0.7 cm/s).3.In order not to affect the normal flight,feeding,horizontal movement and vertical movement of E.brandti,a 6 mg electronic tag should be selected.4.There were no significant differences in the average step length and straight-line index of E.scrobiculatus on the host’s different positions,different ages and different genders.The movement of70 % adult E.brandti is directional,and the movement of 30 % E.brandti is random.It is preliminarily believed that the dispersal of E.brandti also spreads along the direction of the host.The average dispersal rate of E.brandti was greater than that of E.scrobiculatus.