Factors Contributing to the Reemergence of Goss's Wilt and Blight in the Upper Midwestern U.S.

Abstract

Goss’s wilt and blight of corn, caused by the bacterium Clavibacter michiganensis subsp. nebraskensis, is one of the most important bacterial diseases of corn in the U.S. It was first described in Nebraska in 1969 and was a minor problem until its reemergence in 2006. Since then, Goss’s wilt has been reported in many of the major corn producing states and provinces of the U.S. and Canada. Basic information regarding the biology and management of this pathosystem was lacking. The goals of this research were to i) understand the genetic diversity and phylogeny of Clavibacter michiganensis subsp. nebraskensis isolates from the Midwest and Central Plains, ii) understand the pathogenicity and survival of this pathogen on crops, weeds, and native grasses, and iii) determine potential effects of foliar fungicides on the severity of Goss’s wilt. The results help to clarify issues related to the reemergence and management of Goss’s wilt.