A Diagnostic Guide for Berkeleyomyces rouxiae Causing Black Root Rot of Cotton

Abstract

Black root rot (BRR) is a major seedling disease of cotton in Australia. The disease is caused by Berkeleyomyces rouxiae (formerly known as Thielaviopsis basicola), which is morphological identical to B. basicola. In this diagnostic guide, we aim to share current work and understanding of the B. rouxiae in cotton in Australia. This guide includes a comprehensive signs and symptoms to allow correct identification of the disease in the field. Methods and tricks to isolate and purify the pathogen from soil and diseased cotton were also discussed. Additionally, available molecular approaches for accurate identification of B. rouxiae were summarized. Last but not least, methods to preserve and assess pathogenicity of B. rouxiae on cotton were also presented.