The Occurrence Of Spodoptera Frugiperda In Part Of Hunan And The Assessment Of Effect Of Different Control Measures

The Spodoptera frugiperda is a migratory omnivorous pest.In China,it was not found until the beginning of 2019 that it was first detected in Yunnan and caused widespread damage.In order to learn more about S.frugiperda,this study investigated the outbreak areas and potential risk areas of S.frugiperda in Hunan Province,and carried out field tests on the available control reagents and monitoring devices,in order to provide a theoretical basis for the monitoring and control of S.frugiperda in Hunan Province.The main results of this test are as follows:(1)Through the investigation of the disaster situation of S.frugiperda in Zhangjiajie Yongding area,we found that: From May to August 2019,the cumulative disaster area of 24 townships and streets in the district reached 16,504 mu;At the end of May,only 8 streets were affected by S.frugiperda,and the most serious was Houping street that affected by a large-scale outbreak and which caused a disaster about 1500 mu.While the other 7 treets didn’t have a major outbreak which disaster was relatively minor.In mid-to-late June,Spodoptera frugiperda broked out in five places that are Sanjiaguan Township,Siduping Township,Qiaotou Township,Luoshui Township and Jiaoziya Township,which cauesd large-scale disasters.(2)Through the chemical test of the corn planting area in Li County,Changde City,it was found that: The control effect of Bacillus thuringiensis WP was 84.29%after 3 days,which was lower than 5% Bacillus thuringiensis and Indoxacarb SC93.45% in the same period.The control effect of Bacillus thuringiensis WP was93.89% after 7 days,which was lower than 5% Bacillus thuringiensis and Indoxacarb SC 94.90% in the same period.When these two agents are mixed and used,the control effect was 100% after 3 days.The control effects both of them were higher than 85% which indicated them all had good control effects,but the 5% Bacillus thuringiensis and Indoxacarb SC was better.The result of mixed suggested that mixed drugs can also increase control effect.In addition,spiders,ladybird beetles,wasps and other natural enemies were found in the test area,indicating that these two agents have little lethality to beneficial insects and were basically harmless to natural enemies.(3)Through the test of the trapping rate of S.frugiperda different lures in the corn planting area of Li County,Changde City,it was found that: Among the seven different lures,SF20196C1 M and SF20196C1 X can be the best choices,SF20196C1,SF20196C1 F and SF20196C1 H were relatively poor and can be used as alternatives,while SF20196C1 A and SF20196C1 W had poor overall performance and were not recommended for field use.In addition,according to the field survey results after the traps were placed,the traps need a certain period of time to play the role of prevention and control.Therefore,when using sexual traps for field monitoring and control,it needs to be deployed in advance.In conclusion: there is still a possibility of a large-scale outbreak of Spodoptera frugiperda in China.The selected Bacillus thuringiensis WP,5% Bacillus thuringiensis and Indoxacarb SC and the sexual trap can effectively deal with the massive outbreak of Spodoptera frugiperda in this study,and can be used as one of the options for field monitoring and control.