Household air conditioners are known to be contaminated with dematiaceous fungi such as genus Toxicocladosporium and genus Cladosporium. We frequently encounter cases in which a large amount of fungi, which are presumed to belong to the family Cordycipitaceae, are isolated from the blowout air of the household air conditioners. Therefore, the Cordycipitaceae isolated in the survey of four cases of the air conditioners were identified by genetic analyses. As a result, all of them were found to be Simplicillium sympodiophorum. The concentration of airborne fungi, S. sympodiophorum in the blowout air was high (> 10 4 cfu/m 3 ) as exceeding the upper limit of quantification in three of four cases, and 5,000 cfu/m 3 in one case. This study revealed that S. sympodiophorum contaminated multiple air conditioners. Genus Toxicocladosporium was also isolated from the two air conditioners, and it was found to be Toxicocladosporium irritans by the genetic analysis.

Eighty-seven strains of Aspergillus section Restricti were isolated from five storage rooms (50 strains) and 21 houses (37 strains) between 2014 and 2020. Eleven species were identified based on their morphological characteristics and molecular phylogeny using the rRNA internal transcribed spacer (ITS) region, calmodulin (CaM) , β-tubulin (benA) , and RNA polymerase II second largest subunit (RPB2) sequences. A. penicillioides, which was known to cause the deterioration of cultural assets, was isolated at high frequency (73%) from the surfaces of 11 cultural assets in the storage rooms; A. clavatophorus and A. magnivesiculatus, which are closely related to A. penicillioides, were also isolated frequently (45 and 64%, respectively) . Five species ［A. clavatophorus (42.8%) , A. penicillioides (42.8%) , A. magnivesiculatus (14.3%) , A. reticulatus (28.6%) , and A. vitricola (28.6%) ］ were isolated from dust on the carpets in seven houses. Five species ［A. clavatophorus (33.3%) , A. penicillioides (55.5%) , A. magnivesiculatus (44.4%) , A. restrictus (44.4%) , and A. gracilis (11.1%) ］ were isolated from dust on the bedding in nine houses. Using the taxonomic system described by Sklenár ̌ et al. (2017) , five species (A. clavatophorus, A. magnivesiculatus, A. hordei, A. reticulatus, and A. glabripes) previously identified as A. penicillioides were confirmed as new to Japan.

In order to evaluate the potential application of microsporidia as a microbial control agent against lepidopteran insect pests, microsporidian infection in a field population of the common cutworm, Spodoptera litura (Fabricius), was surveyed in vegetable crop fields in Can Tho City, Vietnam, in March 2007. The infection rate of microsporidia was 46.7% (99/212 individuals) in adult S. litura, and 16 samples of infected adults were used to characterize the microsporidia at the molecular level. Analysis of the small subunit ribosomal RNA (SSU rRNA) sequences indicated that microsporidian strains isolated from S. litura were closely related to Nosema bombycis from the silkworm, Bombyx mori (Linnaeus); however, phylogenetic analysis based on genome profiling produced a different result from the SSU rRNA sequences. Temperature gradient gel electrophoresis profiles of 12 microsporidian strains from S. litura were closely related to N. bombycis strains, while the profiles of three microsporidian strains formed a different cluster. The Vietnamese strains did not form a single group, but were classified into at least three groups. These results suggested that the microsporidia isolated from S. litura in the Mekong Delta, Vietnam, are genetically diverse.

Bacillus thuringiensis Berliner has previously been classified via the serological identification of flagellar antigens. However, the phylogenetic relationships among strains of B. thuringiensis cannot be investigated by serotyping. Furthermore, high levels of homology have been found in gene sequences among various strains, complicating the determination of their evolutionary relationships. In order to elucidate the phylogenetic relationships within B. thuringiensis, we analyzed 40 strains belonging to typical serotypes using two approaches: an analysis of small subunit (SSU) rRNA sequences and genome profiling (GP) based on temperature gradient gel electrophoresis of random PCR products. The SSU rRNA analysis resulted in all 40 strains forming a single cluster with Bacillus cereus Frankland & Frankland. The distances among the subclusters were too small to further classify the strains. On the other hand, the phylogenetic analysis based on GP resulted in three clusters of B. thuringiensis strains. These results suggest that GP is a better method for the determination of phylogenetic relationships within B. thuringiensis.

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