Open AccessCercospora nicotianae Isolates from Flue-Cured Tobacco in North Carolina Found with G143A and F129L Mutations in Cytochrome b Gene
Author(s) -
Andrew Ernst,
Lindsey Thiessen
Publication year - 2020
Publication title -
plant health progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.565
H-Index - 9
ISSN - 1535-1025
DOI - 10.1094/php-04-20-0029-rs
Subject(s) - cercospora , biology , fungicide , azoxystrobin , leaf spot , point mutation , curing of tobacco , horticulture , botany , veterinary medicine , mutation , gene , genetics , medicine
Frogeye leaf spot of tobacco caused by Cercospora nicotianae (Ellis & Everhart) is a widespread disease of cultivated tobacco. Recently, flue-cured tobacco producers in North Carolina reported losses due to frogeye leaf spot disease despite the use of strobilurin fungicides. Isolates (n = 4) were obtained in 2018 from affected tobacco leaves from Cumberland, Lenoir, and Nash counties. In 2019, isolates (n = 28) were collected from a field in Wilson county. After sequencing the cytb region of 32 isolates, 30 contained a single point mutation conferring a G143A or F129L amino acid change that resulted in quinone outside inhibitor (QoI) fungicide resistance. Although these resistance mutations have been found in air-cured tobacco in Kentucky, to the best of our knowledge, the present study is the first to report QoI resistance mutations in C. nicotianae populations in flue-cured tobacco and a first report in North Carolina.