Fungi that infect mushrooms and cause diseases are called mycoparasitic fungi. Understanding the diversity of mycoparasitic fungi in wild mushrooms is important for the mushroom industry, as they can parasitize cultivated mushrooms. However, few studies have been conducted on the diversity of mycoparasitic fungi in wild mushrooms in South Korea. Upon surveying mushroom flora, we found a mycoparasitic fungus and analyzed its strain using molecular phylogeny and morphological examination. The strain was identified as Sepedonium laevigatum, which is an unrecorded species in South Korea. In this study, we described the cultural and microscopic characteristics of this strain of fungus.

In some cicada species, male calling songs are so loud that they become a nuisance to city dwellers in Korea. To understand the abundance of cicada species in central Korea, we conducted complete enumeration surveys of exuviae in Hyalessa fuscata, Cryptotympana atrata, Meimuna spp, and Graptopsaltria nigrofuscata. Exuviae collection was conducted in three representative habitats in central Korea: metropolitan, suburban, and country. We collected the exuviae twice with a 10-day interval between samplings in August 2010. Resource-weighted density of each species was calculated based on the area and the number of trees. H. fuscata was the dominant species in all three regions. Resource-weighted densities in metropolitan and suburban regions were much higher than those in the country region, due to H. fuscata and C. atrata. The results of the multivariate general linear models showed that region, date, and the interaction between these two variables were all significant for population densities of cicada species. Unlike the resource-weighted densities, the organism-weighted densities that indicated the intensity that an individual had to share its host with others were much larger than tree-weighted densities for cicada exuviae. Furthermore, there was no significant difference in organism-weighted densities among habitats. The difference between resource-weighted and organism-weighted densities implied that larger proportions of trees were not used by cicada juveniles in the country. Thus, the distributions and abundance of tree host species could be an important factor for cicada density in Korea.

Wolbachia is one of the most common endosymbionts best known to induce several reproductive alterations in its insect hosts. In some cases, the insect hosts harbor more than two strains of the bacterium. The Vollenhovia emeryi ant lives in dead trees and is morphologically subdivided into the long-winged and the short-winged. Interestingly the short-winged morph is free of Wolbachia, but only the long-winged morph is multiple- infected with the Wolbachia bacterium. We sampled four populations of the long-winged morph in Korea and performed pyrosequencing in Multilocus Sequence Typing (MLST), to determine the bacterial strain diversity. Six different gene regions (coxA, fbpA, ftsZ, gatB, hcpA and wsp gene) were targeted and amplified. However, the result shows that diversity of haplotypes is very high. The pyrosequencing approach in MLST, a new method of discriminating Wolbachia strains, is promising to effectively detect multiple infections and rare haplotypes.

The hologenome theory of evolution proposes that an organism is simply not an individual but the totality of numerous microbial symbionts to the host. In fact, the evidence of biochemical and physiological associations between the symbionts and the host has been growing fast in all major taxa. The Vollenhovia emeryi ant is tiny and found nationwide in Korea. The ant can be further categorized by its wing morphology, eg. long-winged and short-winged. Our initial screening process showed that the microbial reproductive manipulator, the Wolbachia bacterium, only infected the long-winged morph. This gave us a good opportunity to investigate the effect of the Wolbachia infection on the bacterial community diversity using the next generation sequencing technique. We find that there are about 180 bacterial symbionts in the short-winged morph. On the other hand, the long-winged morph has only about 20 bacterial symbionts. This implies that the bacterial community diversity may be subject to the existence of Wolbachia. Furthermore, the Wolbachia strain diversity is unexpectedly high. In addition, the bacterial structure difference among castes indicates that there may be labour division even between queens. The results and future research direction will be discussed from the hologenome theory perspective.

The ant species, Vollenhovia emeryi, is distributed in Far East. The species can be divided into two major groups by their wing morphology of reproductives: short-winged and long-winged. A nationwide survey of the species was conducted for analyzing the mitochondrial haplotype diversity and genetic population structure. We collected 91 samples from 40 locations. A total of the 1239 bp partial COI (cytochrome C oxidase 1) region was used for the analyses. We found the total of 21 haplotypes. The mitochondrial haplotypes may correspond to the wing morphology. The genetic population structure examined potential geographic barriers of gene flow such as distance, mountains, rivers and plains which are non-mountain areas to prevent dispersal through mountain range. The result implied that no barriers considered in this study affected differently gene flow. Therefore, the behavioral characteristics of the ant may be the causal constraint of its genetic exchange.