Study on Verticillium longisporum of canola from the first reported farm in North America

Abstract

Verticillium longisporum (Stark) Karapapa et al. 1997, is a soil-borne pathogen of the Brassicaceae family and causes Verticillium stripe of canola. Verticillium longisporum occurs in three distinct hybrid types that differ in pathogenicity and virulence. In North America, V. longisporum is only observed on cabbage, cauliflower and horseradish. This changed dramatically, when in 2014 for the first time, canola infected with V. longisporum was detected at a research farm in Manitoba, Canada. The pathogen concentration, its distribution and the hybrid type at the farm were unknown. Therefore, in 2016, 194 soil samples from the farm were analyzed using real-time PCR analysis to determine pathogen concentration per gram of dry soil. Of the 194 soil samples, the real-time assay reported 39% samples positive for the pathogen. This study also added information on the pathogen hybrid lineage that was determined to be the most aggressive type on canola.