Investigation on the breeding situation of Blattella asahinai in Songjiang District of Shanghai

LYU Xi-hong; GUO Xiao-qin; FEI Sheng-jun; XU Hai-gen; CAI Yun-peng; LI Li; LENG Pei-en

Abstract：Objective To know population composition,density,life history and insecticide susceptibility of Blattella asahinai in Songjiang Chenshan,and accumulate data for reseraching cockroaches species,biology and control in Shanghai.Methods From May 2015 to June 2016,the cockroach house trapping method was used to investigate the population composition and density in the bamboo forest and shrub forest.The captured cockroaches were brought back to the laboratory for identification,enumeration and feeding.The insecticide film contact method was conducted for bioassay.Results The cockroaches were identified as Blattella asiatica by observing the shape of adult male the 7th and 8th abdominal tergal glands.Totally 1 752 cockroaches were trapped in 50％ (310/620) of cockroach traps.The density peak appeared in late August and the over wintering period was about 5 months.The adults in population increased first and then decreased,while nympha were on opposite.The densities in shrub and bamboo habitats showed little differences (t =-0.976,P =0.338).There were 20 to 30 nymphae hatching from one egg sheath.It took three months for the nymph to develop to adult.For 0.05％ beta-cypermethrin,the cockroaches showed lower sensitivity of KT50 5.962 min than German cockroach susceptible strains.Conclusion The density and population composition of Blattella asiatica showed a significant seasonal variation trend.Blattella asiatica might be introduced with plants and trees,and still worth to be conduct study on the phototaxis,life history and pathogens carried.