Effect Of Irradiation On Bacterial And A Junior Study On Advantage Bacteria In The Gut Of Adult Bactrocera Cucurbitae(Coquillett) From The Genetic Sexing Strain(Diptera:Tephritidae)

Bactrocera cucurbitae(Coquillett)is a kind of important agricultural pests.Biological control technique-Sterile Insect Technique(SIT)catch more attentions from relevant agricultural experts at home and abroad,but the irradiation used in SIT impair fitness of fruit flies,there are not detailed reports about this filed.This paper studied the influence on gut bacterial diversity and relative abundance of B.cucurbitae genetic sexing strain(GSS)caused by irradiation,and isolated,identified,selected dominant bacteria to feed B.cucurbitae GSS.Reduced the damage of irradiation to some extent.Main results of this study are as follows:1.Adult females and males from B.cucurbitae GSS at different ages(5-,8-,11-,13-d old respectively)were irradiated by 137Cs with 100 Gy.Illumina MiSeq high-throughput sequencing platform of 16SrDNA was used to study the changes of gut microbial communities caused by irradiation.The results showed that 19 major bacteria genera and 4 phyla were detected in adults’ guts,Proteobacteria(accounted for 50%-98%of the total),Firmicutes(accounted for 2%-47%of the total),Providencia and Enterobacter were dominant bacteria phyla and genera;Irradiation could significantly reduce the diversity and relative abundance of gut symbiotic bacteria,however this result caused by irradiation had nothing to do with sex and adult ages.2.Seven kinds of bacteria general were isolated in 5 days old adult’Guts’ bacteria with microbial traditional separation method,they wre Enterobacter sp.(37%),Providencia sp.(18.5%),Klebsiella sp.(1.9%),Lysinibacillus sp.(1.9%),Cedecea sp.(24%),Bacterium sp.(11.1%)and the other unknown general(5.6%).3.Used Enterobacter sp.as supplement of B.cucurbitae GSS’s larval diet.Designed Probiotic-Irradiated(PI)and Autoclaved(dead)Probiotic-Irradiated(API)as the two treatments,set Nonprobiotic-irradiated(NPI)as a control.When B.cucurbitae GSS changed from pupal to adult after were fed this probiotic diet,measure the biology and morphology indexs.The results showed that PI could significantly increase pupals’ weight,head width and thorax length,API and PI could significantly improve female and male survival rate,the mean persentage were 18%and 4.72%(female),15%and 11%(male)respectively.The results confirmed that Enterobacter sp.was dominant bacteria genera of B.cucurbitae GSS’s gut and also was probiotic bacteria with enhancing the larval diet.Bacause that Enterobacter sp.could be isolated and cultured easily,accounted for the largest proportion(37%)of the total and the significant results in applicable test.All studied results can provide the theoretical proofs for exploring this microbia product as additional agent of B.cucurbitae GSS larval diet,repairing the damage of irradiation to some extent so can enhance sterile adult fitness and use SIT effectivly.