Figure 1.
Composition of the bacterial community present in the larval midgut of M. hippocastani revealed by cloning and sequencing.
(A) Image of the digestion tract of the L3 larvae. Sections used for fluorescence in situ hybridization (FISH) analysis, labeled as ML3 and HL3 are shown. (B) Relative abundance of bacterial classes found in the L2 and L3 larvae. *Low abundant classes: Actinobacteria, Negativicutes and unclassified Bacterioidetes. (C) Total number of operational taxonomic units (OTUs) belonging to each taxonomical family. Asterisks represent groups (phylotypes) shared among samples: black, common to all; red, shared by L2 larvae and adult; blue, shared by L2 and L3 larvae. (D) Rarefaction curve of the total number of OTUs identified in the midgut of the larvae. (E) Rarefaction analysis of the number of bacterial families identified in the midguts of the larvae. (F) Rarefaction curve of the total number of bacterial classes found in the data set against the total number of clones sampled.
Figure 2.
Composition of the bacterial community present in the guts of adult insects.
(A) Image of the digestion tract of the adult gut. Sections used for fluorescence in situ hybridization (FISH) analysis were labeled B1 to B4. (B) Relative abundance of bacterial classes. *Low abundant classes: Acidobacteria, Negativicutes and Alpha proteobacteria. (C) Total of operational taxonomic units (OTUs) belonging to each taxonomical family. Asterisks represent groups (phylotypes) shared among samples: black, common to all; red, shared by L2 larvae and adult; blue, shared by L2 and L3 larvae. (D), (E), and (F) Rarefaction curves of the total number of OTUs, bacterial families and bacterial classes identified in the guts of adult insects.
Table 1.
Richness and diversity indices calculated with the 16S rRNA gene libraries.
Figure 3.
Bacteria in the gut of M. hippocastani, L3 larvae and adult insects.
(A) Number of bacterial foci detected (cell/mm2); probes are listed in Table S3. (B) An image showing Sediminibacterium sp. in the female beetle gut section B1. (C) Image of Achromobacter sp. in female beetle gut section B1. (D) Image of Desulfovibrio sp. in the midguts of L3 larvae. (E) Image of Clostridiales-related clone (p-08) in the hindguts of L3 larvae. (F) Image of another Clostridiales species (p-09) in female beetle gut section B2. Scale bars 20 µm.
Table 2.
Comparison of the bacteria found in Melolontha hippocastani in this study and those described previously in other organisms.