|LEE, THERESA - Rural Development Administration - Korea|
|CHOI, JUNG-HYE - Rural Development Administration - Korea|
|HAM, HYEONHEUI - Rural Development Administration - Korea|
|LEE, SOOHYUNG - Rural Development Administration - Korea|
|HONG, SUNG KEE - Rural Development Administration - Korea|
|RYU, JAE-GEE - Rural Development Administration - Korea|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/30/2016
Publication Date: 11/30/2016
Citation: Lee, T., Ward, T.J., Choi, J., Ham, H., Lee, S., Hong, S., Ryu, J. 2016. Genetic population structure of Fusarium graminearum species complex in Korean cereals [abstract].
Technical Abstract: Small grain cereals are frequently contaminated with toxigenic Fusarium species. Members of the Fusarium graminearum species complex (FGSC) are known as a head blight pathogens and mycotoxin producers. In order to characterize the FGSC populations associated with cereals in Korea, barley, corn, maize, and rice grains were collected from fields at harvest or during storage from 2009 to 2011. The fungal colonies recovered from grain samples were identified based on morphological characteristics and analyses of TEF sequences, and trichothecene chemotype was analyzed using a TRI12 PCR assay. Among 517 FGSC isolates, Fusarium asiaticum accounted for more than 70% of all isolates, and was especially common in barley, wheat, and rice. Most F. asiaticum had the nivalenol chemotype (~85%), while 3-acetyl deoxynivalenol (3-ADON, ~15%) and 15-ADON (<1%) chemotypes were also detected. In corn, however, F. graminearum, was dominant (56%), followed by F. asiaticum (38%). Among F. graminearum isolates from corn, the 15-ADON chemotype was predominant (72%) and 21% had the 3-ADON type. F. vorosii and F. boothii appeared at very low frequency during the test period, and were excluded from further analysis. Analyses of diversity at variable number tandem repeat (VNTR) loci using STRUCTURE confirmed the separation between F. graminearum and F. asiaticum. Individual analyses of each species suggested that F. graminearum had a different and stronger genetic substructure than F. asiaticum. Population analyses using Arlequin revealed that F. asiaticum clusters displayed a low level of differentiation (Fst= 0.08), whereas F. graminearum clusters exhibited a much higher level of genetic differentiation (Fst= 0.23).