Abstract: [Obiective] This study was aimed to exam the structure and diversity of intestinal bacteria community from Atrijuglans hetaohei Yang and Dichocrocis punctiferalis Guenee larvae consuming walnut's green husk. [Method] The 16S rRNA PCR-denaturing gradient gel electrophoresis (PCR-DGGE) and the terminal-restriction fragment length polymorphism (T-RFLP) were employed to investigate the characteristics of intestinal bacteria community from the two main pests. [Results] 1)PCR-DGGE showed that the intestinal tract of A. hetaohei larvae had Wolbachia sp., Enterococcus sp., Enterobacter sp., Rhizobium sp. and Pseudomonas sp., with phylotypes of Wolbachia being the predominant group, accounted for 40% of the measured sequence; the intestinal tract of D. punctiferalis larvae had Wolbachia sp., Enterococcus sp., Rhizobium sp. and Pseudomonas sp., with phylotypes of Enterococcus being the predominant group, accounted for 62.9% of the measured sequence. 2)Phylogenetic analysis of the DGGE band revealed that in all the isolated strains, 72.5% of the strains belonged to Proteobacteria, 12.5% to Firmicutes, and 15% to Bacteroidetes in the intestinal tract of A. hetaohei larvae; 37% of the strains belonged to Proteobacteria and 63% belonged to Firmicutes in the intestinal tract of D. punctiferalis larvae.3)T-RFLP data showed 76 bp and 122 bp T-RFs were the predominant groups in the intestinal tract of A. hetaohei and D. punctiferalis larvae, respectively. Principal component analysis (PCA) and cluster analysis indicated that there were two structure categories for the intestinal bacteria communities in A. hetaohei and D. punctiferalis. 4)Both DGGE and T-RFLP analyses showed the diversity differences of intestinal bacteria from A. hetaohei larvae and D. punctiferalis larvae were not significant, and there was a difference in the proportion of bacteria composition. [Conclusion] This study revealed the characteristics of the intestinal microbial composition in two different insects, which provided a theoretical basis for further study on the relationship between the diets and intestinal microbes of the two different diet larvae consuming walnut's green husk.

Key words: Atrijuglans hetaohei, Dichocrocis punciferalis, intestinal bacteria, PCR-DGGE, T-RFLP