Characterization of Aphanomyces euteiches pathotypes infecting peas in Western Canada
Date
2021Author
Sivachandra Kumar, Nimllash T
Caudillo-Ruiz, Kiela B
Chatterton, Syama
Banniza, Sabine
Publisher
American Phytopathological SocietyType
PreprintPeer Reviewed Status
Peer ReviewedMetadata
Show full item recordAbstract
Aphanomyces root rot, caused by the soil-borne oomycete Aphanomyces euteiches Drechs., has
developed into a serious disease in the pea and lentil-producing areas of the Great Plains of North America. Based on six pea differentials previously used to differentiate 11 pathotypes in France, pathotypes were identified among field isolates from Saskatchewan (14) and Alberta (18). Four isolates from the USA and standard isolates for pathotypes I and III designated in the French study were also included. Each isolate was tested twice in replicated experiments by inoculating French pea differentials Baccara, Capella, MN 313, 902131, 552 and PI 80693, along with the Canadian susceptible pea cultivar CDC Meadow and partially resistant USDA line PI 660736 under controlled conditions. Pea plants grown in vermiculite were inoculated 10 days after seeding by pipetting 5 mL of a suspension containing 1 x 103 zoospores mL-1 to the base of each plant. Root discoloration was scored 10 days post-inoculation using a 0-5 scale. Testing revealed that 38 of the isolates, including standard pathotype I isolate RB84 belonged to pathotype I, 4 isolates including standard pathotype III isolate Ae109 were pathotype III, and USA isolate Ae16-01 was a pathotype II isolate. An alfalfa isolate from Quebec was avirulent on all pea genotypes. These findings indicate that pathotype type I is predominant on the Canadian prairies.
Citation
Sivachandra Kumar NT, Caudillo-Ruiz KB, Chatterton S, Banniza S. (2021). Characterization of Aphanomyces euteiches pathotypes infecting peas in Western Canada. Plant Dis. https://doi.org/10.1094/PDIS-04-21-0874-RE. Online ahead of print.Series/Report No.
Plant Disease;Subject
Pea differentials
breeding
virulence
oomycete