Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

First report of Dickeya dianthicola and Pectobacterium wasabiae causing aerial stem rot of potato in Michigan, USA.

Abstract

Pectolytic Dickeya spp. and Pectobacterium spp. are commercially important seedborne bacteria of potato that cause blackleg, soft rot and aerial stem rot. Dickeya and Pectobacterium spp. have been recovered from potato production fields in parts of the USA, but a better understanding of their distribution is needed. Aerial stem rot can cause economic losses due to poor/weak stands, late emergence and in severe cases non-harvestable fields. The disease has not been a major issue in the USA until a recent outbreak during the 2015 season. A wet June resulted in a high incidence of aerial stem rot in parts of Michigan. Two potato plants exhibiting aerial stem rot from different fields were submitted to the Michigan State University Diagnostic Services for pathogen identification. The causal pathogen were identified as D. dianthicola and P. wasabiae based on genetic and pathogenicity analyses. This is thought to be the first report of D. dianthicola and P. wasabiae causing aerial stem rot of potato in Michigan, USA.