Study On Control Effects Of Four Pesticides Against Termites In Lianyungang

Termite is one of destructive urban pest insect,which has extensive distribution and great damage.In order to control the damage of termites,Regulation of the Control of Termites in Urban Building(The 130th Decree of the Ministry of construction)stipulated:all building projects including construction,reconstruction,extension and decoration in termites' damage areas need to take the prevention treatment into consideration.The announcement about strengthening and regulating the control of termites with organizations from the reconstruction department of housing and urban-rural in Jiangshu province required to practically strengthen the prevention of termites in building projects including construction,reconstruction,extension and decoration and check and exterminate termites in previous houses.This study is designed to determine the extermination effects and application dosages of biphenthrin,imidacloprid,sulfluramid and hexaflumuron for exterminating Reticulitermes speratus,a major termite species in Lianyungang area,to compare the advantage and shortcoming with two exterminating methods,to establish the optimum time for exterminating termites and to explore the methods for exterminating termites in woodland.Results are as follows:(1)Control effects of four pesticidesResults showed these four pesticides had high effects of extermination against R.speratus from Lianyungang area,through the exterminating experiments in different positons in different fields during nine different months(from March to November).Only applying for one time using biphenthrin and imidacloprid in wooden door frame,wooden window frame and wooden floor of the buildings,can kill the whole termite nest.During the termite extermination in woodland,applying for one time in stumps can kill the whole termite nest,while applying in trees for at least two times can kill the whole termite nest.(2)Application dosage of four pesticidesExperiments in Lianyungang showed that the dosages of biphenthrin and imidacloprid for exterminating R.speratus in buildings are 2500 and 4100 mg per m2.For exterminating R.speratus in stumps in woodland,the dosages of biphenthrin and imidacloprid are 2000 and 3200 mg per nest.In trees,the exterminating dosages of biphenthrin and imidacloprid are 4000 and 6400 mg per nest.In the monitoring and control system with the major application of sulfluramid for exterminating R.speratus in buildings,the application dosage is 0.2-2.6 mg per m2;and 7.5-10.5 mg per nest for exterminating R.speratus in woodland.In the monitoring and control system with the major application of hexaflumuron for exterminating R.speratus in buildings,the application dosage is 1.2-16.8 mg per m2;and about 45 mg per nest for exterminating R.speratus in woodland.(3)Having a deep understanding of advantage and shortcoming between the method of chemical barrier and the method of monitoring and control systemThe advantage of the chemical barrier method is short time for extermination,simplicity and convenience for operator;and the shortcoming for this method is a mass of chemical pesticides should be used and a potential risk for environment and health.The chemical barrier method can be adopted for extermination in any time of one year.The advantage of the monitoring and control system method is less usage of pesticides and safety to environment and health;and the shortcoming for this method is frequently checking,long period for extermination,might cause dissatisfy of resident,and high requirement for the installation procedure.If termites creep into the monitoring and control devices for feeding the baits,the whole termite nest would be exterminated.Our experiments verified that the dosage for chemical barrier method with treating the soil,wood,and so on,is 1000 fold of the dosage of the monitoring and control system method.(4)Establishing the best time for exterminating termites in Lianyungang areaAfter comparing with the results of extermination effects of four pesticides against,we found that if using the chemical barrier method for exterminating termites in Lianyungang area,application in any time of one year can kill out termites.If using the monitoring and control system method for exterminating termites in this area,the application time is recommended to be from March to May and from September to November.The recommended application time for extermination in woodland is from May to September.(5)Discussion of exterminating methods of termites in woodlandFor controlling termites in woodland in Lianyungang using chemical barrier method,pesticides should be sprayed once within the scope of 0.5m around stumps(holes)for termites in woodland,and sprayed twice(with an interval of one month)within the scope of 0.5m around tree for termite in living trees,and meanwhile pesticide should be brushed on trees and poured into holes,and then the holes should be blocked.If using the monitoring and control system method,the system should be installed during May-September,and meanwhile the baits should be paid attention for avoiding from light and rain.Our research is helpful for mastering exterminating termites in Lianyungang,applying pesticides rationally,decreasing the risk of pesticides to environment and health,making sure exterminating effect for reducing people property loss,accumulating the experience for the control of termites in local woodland,and providing a basis for better protecting forest resources and reducing the loss caused by termite damage.