Shunsuke Nozawa

Dr. Shunsuke Nozawa


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
5 April 2023 in Journal of Fungi
Verified
Journal Article
Open access
PDF file
SNShunsuke Nozawa
Shunsuke Nozawa
YSYosuke Seto
Yosuke Seto
YTYoshiki Takata
Yoshiki Takata
LNLalaine Albano Narreto
Lalaine Albano Narreto
Reynaldo ValleReynaldo Valle
Reynaldo Valle
KWKyoko Watanabe
Kyoko Watanabe
The pathogen causing Fusarium wilt in banana is reported to be Fusarium oxysporum f. sp. cubense (FOC). In 2019, wilt symptoms in banana plants (cultivar: Cavendish) in the Philippines were detected, i.e., the yellowing of the leaves and discoloration of the pseudostem and vascular tissue. The fungus isolated from the vascular tissue was found to be pathogenic to Cavendish bananas and was identified as a new species, F. mindanaoense, belonging to the F. fujikuroi species complex (FFSC); species classification was assessed using molecular phylogenetic analyses based on the tef1, tub2, cmdA, rpb1, and rpb2 genes and morphological analyses. A reciprocal blast search using genomic data revealed that this fungus exclusively included the Secreted in Xylem 6 (SIX6) gene among the SIX homologs related to pathogenicity; it exhibited a highly conserved amino acid sequence compared with that of species in the FFSC, but not with that of FOC. This was the first report of Fusarium wilt in Cavendish bananas caused by a species of the genus Fusarium other than those in the F. oxysporum species complex.

8 March 2024 in Journal of Fungi
Verified
Journal Article
Open access
PDF file
YTYoshiki Takata
Yoshiki Takata
CPCELYNNE OCAMPO PADILLA
CELYNNE OCAMPO PADILLA
MMMike Andre C. Malonzo
Mike Andre C. Malonzo
DPDan Charlie Joy Camara Pangilinan
Dan Charlie Joy Camara Pangilinan
SNShunsuke Nozawa
Shunsuke Nozawa
KWKyoko Watanabe
Kyoko Watanabe
Similar to cacao pod rot, cherelle wilt decreases production from cacao fields. Among all known fungal pathogens of the cacao, Colletotrichum spp. are common infectious agents that affect the cherelles and pods of cacao; thus, cacao diseases are often classified by stage. Therefore, knowing whether these pathogens are common in both fruit stages is necessary for implementing disease control measures. Symptoms of cherelle wilt were found in cacao plants in Pangasinan, Philippines, in 2022. The fungal strain obtained from the lesion was found to be pathogenic towards cherelles, but not towards pods. The strain was classified as an unknown species belonging to the gigasporum species complex, based on the morphological and molecular phylogenetic analyses of ITS, GAPDH, CHS1, ACT, and TUB2. We propose Colletotrichum kapreanum sp. nov. as a causal agent of cacao cherelle wilt, but not pod rot.

10 March 2026 in Journal of Fungi
Verified
Journal Article
Open access
PDF file
YHYui Harada
Yui Harada
SNShunsuke Nozawa
Shunsuke Nozawa
YTYoshiki Takata
Yoshiki Takata
CPCELYNNE OCAMPO PADILLA
CELYNNE OCAMPO PADILLA
KWKyoko Watanabe
Kyoko Watanabe
The genera Pestalotiopsis, Neopestalotiopsis, and Pseudopestalotiopsis share highly similar morphological characteristics. Although species within these genera are recognized as plant pathogens, their pathogenicity can differ even on the same host plant, highlighting the importance of accurate genus-level identification for effective disease management. However, reliable discrimination among these genera based solely on morphology or internal transcribed spacer (ITS) amplicon length is difficult. Therefore, molecular approaches based on ITS sequence data are required for practical and reliable genus-level identification. This study aimed to develop genus-specific PCR primers through comparative genome analysis using genus-specific gene regions identified from available genomic data. The performance of these primers was evaluated using 49 isolates obtained from banana, Japanese andromeda, loquat, rubber, and tea. The primer sets achieved an overall identification accuracy of 97%. One strain could not be assigned to Pestalotiopsis, which exhibited morphological characteristics inconsistent with the genus and was positioned outside the main Pestalotiopsis clade in phylogenetic analyses, supporting the taxonomic validity of the primer-based identification. These results demonstrate that the developed primers provide a reliable and practical tool for genus-level identification and taxonomic assignment of these morphologically similar fungal pathogens, including direct detection from infected plant tissues.