TY - JOUR
T1 - Identification and characterization of Colletotrichum species causing apple bitter rot in New York and description of C. noveboracense sp. nov.
AU - Khodadadi, Fatemeh
AU - González, Jonathan B.
AU - Martin, Phillip L.
AU - Giroux, Emily
AU - Bilodeau, Guillaume J.
AU - Peter, Kari A.
AU - Doyle, Vinson P.
AU - Aćimović, Srđan G.
N1 - Funding Information:
This material is based upon the work supported by the New York Apple Research and Development Program grant numbers 86698 and 83268 to SGA. This work is supported in part by the New York State Specialty Crop Block Grant Program grant number 89379-P001/SCBG 19 006 to SGA and the SGA’s discretionary program funds. We thank David Lewis for sharing the resources of Vassar College microscopy facility at Biology Department in support of this work and Gillian Turgeon and Kathie Hodge at Cornell University for occasional advising. We acknowledge Keith Yoder at Virginia Polytechnic Institute and State University for providing the diseased apple fruit samples from Virginia. At last, we thank the staff and faculty of Cornell University’s HVRL, Christopher Meredith, Lucas Canino, Ricardo Delgado Santander, David Rosenberger and Peter Jentsch for help collecting and mapping apple samples or supporting this research at its initial stages. We acknowledge all apple growers for supporting this work directly or indirectly by allowing access to their farms, contributing HVRL membership and donations, funding facility upgrades and maintenance of HVRL laboratories and experiment plots.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Apple bitter rot caused by Colletotrichum species is a growing problem worldwide. Colletotrichum spp. are economically important but taxonomically un-resolved. Identification of Colletotrichum spp. is critical due to potential species-level differences in pathogenicity-related characteristics. A 400-isolate collection from New York apple orchards were morphologically assorted to two groups, C. acutatum species complex (CASC) and C. gloeosporioides species complex (CGSC). A sub-sample of 44 representative isolates, spanning the geographical distribution and apple varieties, were assigned to species based on multi-locus phylogenetic analyses of nrITS, GAPDH and TUB2 for CASC, and ITS, GAPDH, CAL, ACT, TUB2, APN2, ApMat and GS genes for CGSC. The dominant species was C. fioriniae, followed by C. chrysophilum and a novel species, C. noveboracense, described in this study. This study represents the first report of C. chrysophilum and C. noveboracense as pathogens of apple. We assessed the enzyme activity and fungicide sensitivity for isolates identified in New York. All isolates showed amylolytic, cellulolytic and lipolytic, but not proteolytic activity. C. chrysophilum showed the highest cellulase and the lowest lipase activity, while C. noveboracense had the highest amylase activity. Fungicide assays showed that C. fioriniae was sensitive to benzovindiflupyr and thiabendazole, while C. chrysophilum and C. noveboracense were sensitive to fludioxonil, pyraclostrobin and difenoconazole. All species were pathogenic on apple fruit with varying lesion sizes. Our findings of differing pathogenicity-related characteristics among the three species demonstrate the importance of accurate species identification for any downstream investigations of Colletotrichum spp. in major apple growing regions.
AB - Apple bitter rot caused by Colletotrichum species is a growing problem worldwide. Colletotrichum spp. are economically important but taxonomically un-resolved. Identification of Colletotrichum spp. is critical due to potential species-level differences in pathogenicity-related characteristics. A 400-isolate collection from New York apple orchards were morphologically assorted to two groups, C. acutatum species complex (CASC) and C. gloeosporioides species complex (CGSC). A sub-sample of 44 representative isolates, spanning the geographical distribution and apple varieties, were assigned to species based on multi-locus phylogenetic analyses of nrITS, GAPDH and TUB2 for CASC, and ITS, GAPDH, CAL, ACT, TUB2, APN2, ApMat and GS genes for CGSC. The dominant species was C. fioriniae, followed by C. chrysophilum and a novel species, C. noveboracense, described in this study. This study represents the first report of C. chrysophilum and C. noveboracense as pathogens of apple. We assessed the enzyme activity and fungicide sensitivity for isolates identified in New York. All isolates showed amylolytic, cellulolytic and lipolytic, but not proteolytic activity. C. chrysophilum showed the highest cellulase and the lowest lipase activity, while C. noveboracense had the highest amylase activity. Fungicide assays showed that C. fioriniae was sensitive to benzovindiflupyr and thiabendazole, while C. chrysophilum and C. noveboracense were sensitive to fludioxonil, pyraclostrobin and difenoconazole. All species were pathogenic on apple fruit with varying lesion sizes. Our findings of differing pathogenicity-related characteristics among the three species demonstrate the importance of accurate species identification for any downstream investigations of Colletotrichum spp. in major apple growing regions.
UR - http://www.scopus.com/inward/record.url?scp=85087498112&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85087498112&partnerID=8YFLogxK
U2 - 10.1038/s41598-020-66761-9
DO - 10.1038/s41598-020-66761-9
M3 - Article
C2 - 32632221
AN - SCOPUS:85087498112
SN - 2045-2322
VL - 10
JO - Scientific reports
JF - Scientific reports
IS - 1
M1 - 11043
ER -