Study On The Symbiotic Bacteria Population Change And Insecticide Resistance Of Blattella Germannica

Blattella germanica is hardest control and strongest insecticide resistance ofBlattaria. Blattella germanica’s infringement to human have been grave with eachpassing day. At present, human abuse a lot of pesticides, Blattella germanica havesignificant resistance to insecticides and increase the difficulty to control. Thereforehow to control the Blattella germanica has become an urgent problem to be solved,we face new issues and challenges.In order to eliminate the Blattella germanica, weshould base on the resistance of the occurrence, development and resistance level towork out a reasonable control strategy, on this basis, from a different point of researchon a new method of eliminating Blattella germanica. The symbiotic bacteria ofBlattella germanica is an important part of insect ecology, with a variety of relationsand insects, plays an important biological role of the absorption and utilization ofnutrients, to resist invasion and colonization of foreign bacteria,promote immunesystem function. This paper will research on intestinal flora, to study it effects onresistance of Blattella germanica, which can provide a new way for the preventionand control of Blattella germanica, has important practical application significance.In this paper, sensitive and resistant strains of Blattella germanica as the objectof study. We evaluate the removal efficiency of intestinal flora in Blattella germanicausing three antibiotics, rifampicin, gentamicin and penicillin in differentconcentrations. The study should obtain the intestinal flora free population of Blattellagermanica. We study the differences in resistance and biological fitness aspects ofsensitive and resistant strains. Finally, the paper studied the microbial communitystructure in the differences of sensitive and resistant strains of Blattella germanicaintestinal bacterial community structure. The mainly research contents and results areas follows:(1)We research the removal efficiency of intestinal flora in Blattella germanicausing different antibiotics. At a concentration of200.0μg/mL and500.0μg/mL,gentamicin can respectively remove the male and female intestinal flora one hundredpercent without causing the normal life of Blattella germanica. We can obtain the intestinal flora free population of Blattella germanica. Through the experiment,female Blattella germanica’s intestinal bacteria removal time is long and the use ofhigh concentration of antibiotics.(2)In this study, symbiotic bacteria of Blattella germanica effect insecticideresistance and biotic fitness. Cypermethrin, propoxur and DDVP have an effect on S,R, D-S and D-R strains of Blattella germanica. KT50of removing the intestinalbacteria of Blattella germanica was lower than susceptible strains, insecticideresistance of it is low.Intestinal bacteria have a significant effect of Blattellagermanica. From the perspective of biotic fitness, little change in Egg pods off time,egg pod length, adult weight. The larvae hatch number reduced, larva eclosion ratelow, female offspring decrease, fecundity of removal the intestinal bacteria reduced.Intestinal bacteria influenced Blattella germanica’s growth. Removal intestinalbacteria strains of the mortality rate of larvae was higher, the growth period is longer.(3)The paper studied the microbial community structure in two strains ofBlattella germanica by PCR-DGGE.The two strains are different of electrophoresisband number and mobility. Treated with insecticides can change the types andquantity of microorganism in vivo of Blattella germanica.