Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Nishi Oumi Last modified date:2024.06.03

Assistant Professor / Laboratory of Insect Pathology and Microbial Control, Institute of Biological Control / Department of Bioresource Sciences / Faculty of Agriculture

1. Iida Y, Higashi Y, Nishi O, Kouda M, Maeda K, Yoshida K, Asano S, Kawakami T, Nakajima K, Kuroda K, Tanaka C, Sasaki A, Kamiya K, Yamagishi N, Fujinaga M, Terami F, Yamanaka S and Kubota M, Entomopathogenic fungus Beauveria bassiana–based bioinsecticide suppresses severity of powdery mildews of vegetables by inducing the plant defense responses, Front. Plant Sci., 10.3389/fpls.2023.1211825, 14, 1211825, 2023.08, The entomopathogenic fungus Beauveria bassiana is used commercially as a microbial insecticides against a wide range of agricultural insect pests. Some strains of B. bassiana protect the plants from pathogens, but the underlying mechanisms are largely unknown. Here, we found that prophylactic sprays of commercial bioinsecticide Botanigard on cucumber, tomato, and strawberry plants suppressed the severity of economically damaging powdery mildews. On leaf surfaces, hyphal elongation and spore germination of cucumber powdery mildew, Podosphaera xanthii , were inhibited, but B. bassiana strain GHA, the active ingredient isolated from Botanigard, only inhibited hyphal elongation but had no effect on spore germination of P. xanthii . In addition, strain GHA suppressed powdery mildew symptoms locally, not systemically. Treatment with Botanigard and strain GHA induced a hypersensitive response (HR)–like cell death in epidermal cells of the cucumber leaves in a concentration-dependent manner and inhibited penetration by P. xanthii . Transcriptome analysis and mass spectrometry revealed that GHA induced expression of salicylic acid (SA)–related genes, and treatment with Botanigard and GHA increased the SA level in the cucumber leaves. In NahG -transgenic tomato plants, which do not accumulate SA, the biocontrol effect of tomato powdery mildew by GHA was significantly reduced. These results suggested that B. bassiana GHA induces SA accumulation, leading to the induction of HR-like cell death against powdery mildew and subsequent suppression of fungal penetration. Thus, Botanigard has the potential to control both insect pests and plant diseases..
2. Mulue Girmay Gebreslasie,Oumi Nishi,Naoya Wasano,Chisa Yasunaga‐Aoki, Varied selectivity of caterpillar‐specific Metarhizium rileyi and generalist entomopathogenic fungi against last instar larvae and pupae of common cutworm, Spodoptera litura (Lepidoptera: Noctuidae), Applied Entomology and Zoology, 10.1007/s13355-023-00824-x, 58, 219-228, 2023.04, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is a serious pest of crops and vegetables in several Asian areas. Metarhizium rileyi is one of the most promising entomopathogenic fungi for controlling S. litura because of its specificity to lepidopteran larvae; however, little is known about its virulence against last instar larvae and pupae of S. litura although these stages are efficiently controlled by introducing entomopathogenic fungi into the soil. This study aimed to characterize the virulence of M. rileyi strain against the two stages of S. litura by comparing it with 13 strains of entomopathogenic fungi with broad host ranges. In inter-stage virulence comparisons, most fungal strains showed considerably stronger virulence against larvae than against pupae, with M. rileyi Nr4 showing the largest difference. Inter-strain virulence comparisons based on final mortality and mycosis proportion as well as integrative virulence scores revealed that M. rileyi Nr4 was the most virulent against larvae, whereas it was the weakest against pupae, but caused malformation in emerged adults. These results suggest that M. rileyi Nr4 is the most promising for controlling the last instar larvae and is less effective against pupae than the generalist fungi..
3. 西 大海, 須志田浩稔, 東佑実子, 飯田祐一郎, Entomopathogenic fungus Akanthomyces muscarius (Hypocreales: Cordycipitaceae) strain IMI 268317 colonises on tomato leaf surface through conidial adhesion and general and microcycle conidiation , Mycology, 10.1080/21501203.2021.1944929, 13, 2, 133-142, 2022.06.
4. 川原顕生, 飯山和弘, 浅野眞一郎, 西 大海, 青木智佐, Detection of cry-type gene homologues in the draft genome sequence of Paenibacillus popilliae ATCC 14706T and trial for the expression of recombinant proteins in Escherichia coli, Journal of Insect Biotechnology and Sericology, 89, 25-30, 2020.01.
5. Maximiano Corrêa Cassal, Airi Fukushima, Oumi Nishi, Kazuhiro Iiyama, Lidia Mariana Fiuza, Chisa Yasunaga-Aoki, Identification and characterization of three microsporidian genera concurrently infecting a silkworm, Bombyx mori, in Brazil , Journal of Invertebrate Pathology, 10.1016/j.jip.2020.107502, 177, 107502, 2020.11.
6. Oumi Nishi*, K. Iiyama, C. Yasunaga-Aoki, S. Shimizu, Abundance of the soil entomopathogenic fungus Metarhizium anisopliae sensu lato in agricultural field and forest soils in Japan, Current Research in Environmental and Applied Mycology, 10.5943/CREAM/8/4/6, 8, 4, 468-473, 2018.01, Metarhizium anisopliae sensu lato is a facultative entomopathogenic, soil-inhabiting fungus that has been used for biological control of soil-dwelling arthropod pests. However, little is known about the density of M. anisopliae sensu lato in forest soils and the difference in the density among different habitat types and geographical origins. In this study, we determined the density of this fungus in soil samples collected from forest and agricultural fields in Japan by plating method with semi-selective agar medium and analyzed its associations with the habitat types and latitudes of the collecting sites. Mean and mode density of 211 soil samples were 9.4 × 10 2 CFUs/g soil and 1.0 × 10 3 -1.0 × 10 4 CFUs/g soil, respectively, which were comparable to the levels previously reported in other countries. The density in forest soil was not significantly different from that of the other habitat types, despite previous studies that concluded M. anisopliae sensu lato to be less abundant in forest soil based on occurrence determined by insect bait method. The latitude was also not significantly associated with the density. This study revealed higher abundance of M. anisopliae sensu lato in forest soil than the original expectation..
7. Iida Y*, Ikeda K, Sakai H, Nakagawa H, Nishi O, Higashi Y, Evaluation of the potential biocontrol activity of Dicyma pulvinata against Cladosporium fulvum, the causal agent of tomato leaf mold, Plant Pathology, 10.1111/ppa.12916, 67, 9, 1883-1890, 2018.12, [URL].
8. NISHI Oumi*, SATO Hiroki, Isolation of Metarhizium spp. from rhizosphere soils of wild plants reflects fungal diversity in soil but not plant specificity, Mycology, 10.1080/21501203.2018.1524799, 10, 1, 22-31, 2018.09, [URL].
9. NISHI Oumi*, IIYAMA Kazuhiro, YASUNAGA-AOKI Chisa, SHIMIZU Susumu, Abundance of the soil entomopathogenic fungus Metarhizium anisopliae sensu lato in agricultural field and forest soils in Japan, Current Research in Environmental & Applied Mycology, 10.5943/cream/8/4/6, 8, 4, 468-473, 2018.08, [URL].
10. Oumi Nishi*, Hiroki Sato, Species diversity of the entomopathogenic fungi Metarhizium anisopliae and M. flavoviride species complexes isolated from insects in Japan, Mycoscience, 10.1016/j.myc.2017.06.008, 58, 6, 472-479, 2017.11, Phylogenetic analyses of insect-derived isolates of the Metarhizium anisopliae and M. flavoviride species complexes in Japan were conducted to reveal their species diversity. Fifty-seven isolates were identified as nine species, including one species first reported for Japan. Metarhizium pingshaense was the most frequently isolated species from this genus, and the 29 isolates of M. pingshaense came from six orders and 14 families of insects. New host–pathogen associations were found for two species with relatively narrow host ranges: Hymenoptera-M. pemphigi, Orthoptera- and Phasmatodea-M. majus..
11. Oumi Nishi*, Susumu Shimizu, Hiroki Sato, Metarhizium bibionidarum and M. purpureogenum
new species from Japan, Mycological Progress, 10.1007/s11557-017-1333-x, 16, 10, 987-998, 2017.10, Two new species of Metarhizium, M. bibionidarum and M. purpureogenum are described from Japan. Metarhizium bibionidarum is the phylogenetic sister species of M. pemphigi and a member of the M. flavoviride species complex. It is distinguished morphologically from M. pemphigi by its larger conidia. The species is based on a collection of an infected March fly larva (Diptera: Bibionidae) but is also known to occur on fruit beetle (Coleoptera: Scarabaeidae) encountered in France. Metarhizium purpureogenum was isolated from soil by plating and insect baiting methods and represents a unique phylogenetic lineage placed outside the M. anisopliae and M. flavoviride species complexes. Three isolates of M. purpureogenum excreted a distinctive red-purple pigment into agar medium when co-cultured with M. robertsii or Aspergillus oryzae..
12. Oumi Nishi*, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, Susumu Shimizu, Species associations and distributions of soil entomopathogenic fungi Metarhizium spp. in Japan, Mycology, 10.1080/21501203.2017.1386244, 8, 4, 308-317, 2017.10, Metarhizium Sorokīn (Hypocreales: Clavicipitaceae) is a genus of facultative parasites of insects found in soils from various environments and is used for pest management. Understanding the habitat selection of Metarhizium spp. is critical to improve the efficacy and persistence of these fungi as microbial insecticides. This study sought to determine the habitat preferences of Metarhizium spp. in Japan. We identified 302 isolates of Metarhizium spp. as eight species by a combination of PCR–RFLP and phylogenetic analysis of DNA sequences. M. pingshaense was the predominant species in Japan and was most frequently isolated from both forest and agricultural environments. On the other hand, M. brunneum and M. pemphigi were comparatively restricted to forest environments. A similar species association was detected in a small area that was intensively investigated, where 7 species including 14 genotypes were isolated from soil. The results of this study have revealed different habitat preferences among Metarhizium spp. in Japan..
13. Oumi Nishi*, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, Susumu Shimizu, Phylogenetic status and pathogenicity of Metarhizium majus isolated from a fruit beetle larva in Japan, Mycological Progress, 10.1007/s11557-015-1082-7, 14, 8, 2015.08, Some isolates of Metarhizium anisopliae sensu lato with large conidia (MALC), which was formerly known as M. anisopliae var. majus, from a scarabaeid host, such as isolates from the coconut rhinoceros beetle (Oryctes spp.), have a narrow host range and are particularly adapted to their original host. Despite recent taxonomic revisions of the genus Metarhizium on the basis of DNA sequences, variations in host preferences of MALC have not been linked to DNA sequence variations. This study focused on the phylogenetic status and pathogenicity of MALC isolated from the fruit beetle larva Protaetia orientalis submarumorea (Pos) in Japan to investigate the relationship between virulence and nucleotide sequence variation among MALC. On the basis of the results of the phylogenetic analyses of DNA sequences from five loci, we identified an isolate from Pos (Hn1) as M. majus, which comprised many isolates with large conidia from scarabaeid insects. In the virulence assay of genetically diverse Metarhizium isolates, only Hn1 and its most closely related isolates from soil showed pathogenicity to Pos; however, these Pos-pathogenic isolates showed weak virulence against silkworms. In the analysis of the intergenic spacer region of rDNA, the Pos-pathogenic isolates displayed unique sequence variation and were clearly distinguished from closely related lineages, including isolates from Oryctes sp., which formed a separate monophyletic group. These results indicate that the Pos-pathogenic isolates from Japan are particularly adapted to Pos and can be genetically distinguished from M. majus isolates from different scarabaeid insects..
14. Oumi Nishi*, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, S. Shimizu, Comparison of the germination rates of Metarhizium spp. conidia from Japan at high and low temperatures, Letters in Applied Microbiology, 10.1111/lam.12150, 57, 6, 554-560, 2013.12, The knowledge of the growth characteristics of entomopathogenic fungi at different temperatures is very important for understanding their ecology and field efficacy as biological control agents. However, the relationships between their DNA-based phylogenetic tree classifications and growth characteristics at different temperatures have not been adequately investigated. In this study, we compared the phylogenetic relationships between Metarhizium anisopliae sensu lato and M. flavoviride isolates obtained from soils in various environments in Japan and the germination rates of their conidia on agar medium in hot and cold conditions. The results showed that the 89 Japanese isolates belonged to the clade of eight species, according to the molecular phylogenetic analysis. The germination rates of isolates belonging to the M. brunneum and M. flavoviride var. pemphigi clades were higher at lower temperatures (9·7-11·0°C) and lower at higher temperatures (34·3-35·2°C) compared with the other six species. The isolates of these two species originated from different geographical regions in Japan, despite their uniform germination characteristics. This study detected the clear interspecific differences in the in vitro germination characteristics of the Japanese isolates of Metarhizium spp. at two different temperature regimes..
15. Kazuhiro Iiyama*, Oumi Nishi, Hiroaki Mon, Man Lee, Takahiro Kusakabe, Shin Ichiro Asano, Chisa Yasunaga-Aoki, Susumu Shimizu, Phylogenetic analysis of Paenibacillus popilliae and its related taxa based on housekeeping genes, Journal of Insect Biotechnology and Sericology, 10.11416/jibs.82.1_001, 82, 1, 1-11, 2013.08, Four housekeeping genes including gapA, groEL, gyrA and pgi were used in order to reveal a phylogenetic relationship among Paenibacillus species. Phylogenetic analysis and end-to-end pairwise analysis were carried out using nucleotide and amino acid sequences of the housekeeping genes. A monophylogenetic clade including P. popilliae, P. thiaminolyticus and P. dendritiformis formed in all phylogenetic trees. The results in both analyses indicated that the relationship between P. larvae subsp. larvae and P. popilliae was comparatively far. The result of the end-to-end pairwise analysis also showed that, among the Paenibacillus species used in this study, the closest species to P. popilliae was P. dendritiformis..
16. Hiroaki Mon, Man Lee, Mai Fukushima, Yudai Nagata, Mie Fujii, Jian Xu, Omi Nishi, Kazuhiro Iiyama, Takahiro Kusakabe*, Production and characterization of the celery mismatch endonuclease CEL II using baculovirus/silkworm expression system, Applied Microbiology and Biotechnology, 10.1007/s00253-012-4583-1, 97, 15, 6813-6822, 2013.08, Mutation and polymorphism detection by nucleases has become a more important tool in clinical and biological researches. There are several kinds of single-stranded nucleases for detecting mismatched DNAs. One of them, CEL II, was isolated from Apium graveolens and cleaves DNA with high specificity at sites of mismatch. High-throughput mutation scanning requires large quantity of CEL II endonuclease. Here, we demonstrate high-level expression of CEL II using silkworm-baculovirus system. The recombinant CEL II secreted in silkworm hemolymph was glycosylated and susceptible to N-glycosidase F. Additionally, larger metal ions such as Ca2+ and Sr2+ were able to replace Mg2+ and enhanced mismatch cleavage activity of CEL II. These results indicate that the silkworm-baculovirus platform is a good alternative system to obtain the functional CEL II..
17. Oumi Nishi, Keiichi Hasegawa, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, Susumu Shimizu*, Phylogenetic analysis of Metarhizium spp. isolated from soil in Japan, Applied Entomology and Zoology, 10.1007/s13355-011-0045-y, 46, 3, 301-309, 2011.08, As a result of analyzing the internal transcribed spacer (ITS) and 5′ end of the EF-1α sequence of 145 isolates of Metarhizium spp. isolated from soil in Japan using selective agar medium, eight species were identified. ITS sequence analysis divided the isolates into three clades. Two were identified as M. flavoviride var. pemphigi and M. lepidiotae, respectively. EF-1α sequence analysis identified the other clades as six species: M. anisopliae, M. brunneum, M. guizhouense, M. majus, M. pingshaense and M. robertisii. The distribution of M. flavoviride var. pemphigi was restricted to forest or wood soil, and conidial sizes of M. guizhouense and M. majus were incongruent with the phylogeny based on the sequence of the 5′ end of EF-1α..
18. Oumi Nishi, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, S. Shimizu*, Incongruence of EF-1α phylogeny and morphology between Metarhizium guizhouense and M. majus, Entomotech, 34, 19-23, 2010.02.
19. Oumi Nishi, Kazuhiro Iiyama, Chisa Yasunaga-Aoki, S. Shimizu*, Virulence of Metarhizium anisopliae var. majus isolated from soils against termite, Coptotermes formosanus Shiraki, Japanese Journal of Environmental Entomology and Zoology, 21, 29-35, 2010.01.