|Manamgoda, Dimuthu - Mae Fah Luan University|
|Rossman, Amy - Retired ARS Employee|
|Crous, Pedro - Central Office For Fungal Cultures (CBS)|
|Madrid, Hugo - Central Office For Fungal Cultures (CBS)|
|Lei, Cai - Chinese Academy Of Sciences|
|Chukeatirote, Ekachai - Mae Fah Luan University|
|Hyde, Kevin - Mae Fah Luan University|
Submitted to: Studies in Mycology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2014
Publication Date: 11/13/2015
Citation: Manamgoda, D., Rossman, A.Y., Castlebury, L.A., Crous, P.W., Madrid, H., Lei, C., Chukeatirote, E., Hyde, K.D. 2014. The genus Bipolaris. Studies in Mycology. 79(1):221-288.
Interpretive Summary: Fungi in the genus Bipolaris occur on a number of important grass crops, including maize, rice and wheat. Species of Bipolaris on staple crops such as rice and wheat have been the cause of historical famines resulting in the starvation of large human populations in several regions in the world. Because many species in this genus have similar microscopic appearances, they have traditionally been identified based on their host plant. This has led to much confusion as some species are able to infect multiple plant species. Using DNA sequences and spore characteristics, we were able to accurately identify 46 species of Bipolaris on a large number of host plants. New descriptions and illustrations are included for 37 of these species. This research will be used by extension agents, plant breeders, plant pathologists, and plant quarantine officials to implement management strategies for diseases caused by these species and to accurately determine the presence of these species in the United States and other countries.
Technical Abstract: The genus Bipolaris includes important plant pathogens with worldwide distribution. Species recognition in the genus has been uncertain due to the lack of molecular data from ex-type cultures as well as overlapping morphological characteristics. In this study, we revise the genus Bipolaris based on DNA sequence data derived from living cultures of fresh isolates, available ex-type cultures from worldwide collections and observation of type and additional specimens. Combined analyses of ITS, GPDH and TEF gene sequences were used to reconstruct the molecular phylogeny of the genus Bipolaris for species with living cultures. The GPDH gene is considered to be the best single marker for species of Bipolaris. Generic boundaries between Bipolaris and Curvularia are revised and presented in an updated combined ITS and GPDH phylogenetic tree. We accept 46 species in the genus Bipolaris and clarify the taxonomy, host associations, geographic distributions and species synonymies. Modern descriptions and illustrations are provided for 37 species in the genus and notes are provided when recent descriptions are available for the other taxa. Bipolaris chloridis, B. cynodontis, B. maydis, B. salviniae, B. victoriae and B. yamadae are epi- or neotypified and lectotypes are designated for B. hadrotrichoides and B. stenospila. Excluded and doubtful species are listed with notes on taxonomy and phylogeny. A taxonomic key is provided for the morphological identification of species within the genus.