Reoccurring wilt: The Eutypella story

Abstract

Reoccurring wilt is a recently described lethal disease of cotton, first detected in Central Queensland in the 2017/18 season. Pathogen identification was established on sequences of the ITS region of rDNA, revealing the presence of two novel Eutypella species. In Qld, the disease has since been detected in St George, Darling Downs, and Border Rivers region. Sequencing of roots and rhizosphere soil from diseased field grown cotton and the adjacent soil, indicated that the pathogen dominated the root microbiome but was not present in the rhizosphere or surrounding soil. Spore traps were strategically placed in-field to determine the presence of Eutypella ascospores. The source of inoculum and transfer of pathogen will be discussed. This study expands current knowledge on epidemiology of Eutypella spp. and provides information for developing management strategies against Reoccurring wilt.