Study On The Occurrence Rule And Control Technology Of Pepper Aphid In Youyang,Chongqing

The aphid is the major pest of Zanthoxylum bungeanum.It has very strong fecundity.According to the investigation over the years,the yield of pepper aphid is reduced by 10%-25% in general,and more than 50% in serious cases.Because aphids occur all year round,and generations overlap seriously,they are very easy to produce resistance to insecticides.At the same time,with the continuous improvement of the cultivation techniques and conditions of Zanthoxylum bungeanum,and the instability of the climate in recent years,the population dynamics of Zanthoxylum bungeanum aphid mixed population is also changing,the harm of Zanthoxylum bungeanum aphid is increasing year by year,which brings great difficulties to the control work.Through the investigation and analysis of the occurrence of aphids in Pepper planting bases in 5key towns of Youyang County,this thesis grasps the key period of pepper Aphids Control,compares the control effects of several control chemicals,and carries out the screening of high-efficiency and low-toxic chemicals,aiming to provide scientific reference for the comprehensive control of pepper aphids in the county,reduce costs,improve the output and yield of green pepper Quality to ensure the increase of farmers' income.1.Through the investigation of five key pepper planting town bases and other surrounding pepper Planting Farmers in Youyang area of Chongqing,the occurrence rule and routine control situation of pepper aphid in Youyang area of Chongqing were learned.Two kinds of aphids have been identified in Pepper trees.One is the cotton aphid(Aphis gossypii Clover)and the other is the orange aphid Toxoptera eitffcidus,which belongs to the Hemiptera,Aphidae.A small number of aphids were found in the planting area of Zanthoxylum bungeanum in the middle of March.At this time,the aphid activity was relatively slow,the range of activity was narrow,and the harm was not obvious.With the increase of temperature,the number of aphids increased from less to more,andthe winged aphids appeared in succession.From April to May,the number of aphids increased,the migration energy increased,and the damage degree was more obvious.In Youyang area of Chongqing,there is a large amount of rainfall from March to June,and there are many days of rainfall.Although it is very difficult to control the pepper aphid,the occurrence of the pepper aphid is significantly reduced due to the continuous rain,and the damage degree is significantly lighter than that of the pepper aphid after the new branches are collected and extracted from the lower branches in July.In the east of Youyang,the altitude is relatively low and the temperature is slightly high.The aphids appear earlier than in the west of Youyang.The west of Youyang is a mountainous area.Affected by the microclimate in the mountainous area,the occurrence of pepper aphids is different,which brings great difficulties to the company's unified guidance of planting.The management level is low,the overuse of chemical fertilizer leads to the growth of trees,excessive extraction of young branches,large amount of aphids,inadequate awareness of plant protection,and the excessive use of chemical pesticides due to the experience or random use of drugs.2.The drug screening was carried out in the pepper Park of Chongqing Hexin Agricultural Development Co.,Ltd.in quankong village,Suixi Town,the key planting area of pepper in Youyang,Chongqing.Through the test of three different chemicals used by pepper farmers in the survey,it was concluded that the dosage was applied when the control effect was good.To avoid pepper farmers in the production process at will to increase the dosage.The results showed that10% chlorothialine wettable powder,50% imidacloprid wettable powder and 25% Pymetrozine suspension had better control effect on the Chinese prickly ash aphid;25% Pymetrozine suspension had the best control effect,followed by 10% chlorothialine wettable powder,and finally 50%imidacloprid wettable powder;considering the control effect and cost of the Chinese prickly ash aphid,10% chlorothialine wettable powder was recommended The aphid of Zanthoxylum bungeanum planting base in Youyang District of Chongqing was controlled by 1500 or 1500 times of imidacloprid WP.