Responses of grass and maize roots to invasion by Gaeumannomyces graminis and Phialophora radicicola

Abstract

The ability of Gaeumannomyces graminis (Sacc.) Arx & Olivier var. tritici Walker, Phialophora radicicola Cain var. graminicola Deacon and P. radicicola var. radicicola to invade roots of Zea mays L. and five species of grass was investigated. All three fungi were restricted to the outer cortex of maize roots but were able to cross the whole cortex of grass roots. Subsequently, G. graminis var. tritici consistently progressed into the stele of grass roots, whereas P. radicicola var. radicicola only did so occasionally and P. radicicola var. graminicola was arrested at the endodermis. Effects of these interactions on the populations of these fungi are discussed.