In order to investigate the diversity of the intestinal aerobic bacteria of the 5th instar larvae of Dendrolimus kikuchii

Matsumura the characteristic ARDRA fingerprint of the larvae’s intestinal bacteria was obtained by amplifying 16S rDNA with

a general primer and digesting the 16S rDNA PCR amplicon (about 15 kb) with four restriction enzymes (Hae Ⅲ, Hind Ⅲ,

HinfⅠ and TaqⅠ). ARDRA patterns were analyzed by MVSP software using the UPGMA method，and the full complement of 5

representative strains’ 16S rDNA were sequenced and blasted in GenBank. Although a few enzyme combinations (Hae Ⅲ + Hind

Ⅲ and  Hinf Ⅰ + Taq Ⅰ) could not completely digest the 16S rDNA PCR amplicon, the diversity of intestinal bacteria could

be inferred from the results obtained from all four restriction enzymes. The results of phylogenetic analysis based on

sequencing show that intestinal aerobic bacteria from the 5th instar larvae of D. kikuchii include Klebsiella oxytoca,

Yokenella regensburgei, Klebsiella peneumoniae, Citrobacter freundii and Bacillus thuringiensis. This diverse intestinal

microbial ecosystem may help protect larvae from invasion by invasive pathogenic bacteria.