Pathotype-characterization of Fusarium oxysporum f. sp. lentis (Fol) Isolates in North America

Abstract

Fusarium wilt caused by Fusarium oxysporum f. sp. lentis (Fol) is a devastating disease of lentils impacting yield in the Northern Great Plains. Characterizing the different pathotypes of Fol and their distribution is an essential part of breeding for resistant cultivars. To date, there has been no characterization of Fol pathotypes in North America. Using a lentil differential set from the International Center for Agriculture Research in Dry Areas (ICARDA), fifty-one pathogenic isolates of Fol from Canada, Montana, Washington, and North Dakota were characterized basing on virulence assessed on foliar wilt symptoms using a Disease Index (DI). Nine pathotypes were identified whereby pathotype 7 was highly virulent on all the differential sets and the most predominant at 55%. This study identified for the first time Fol pathotypes present in North America. These findings will help in future efforts for Fusarium wilt management in lentils.