Establishment of a Fusarium graminearum Infection Model in Arabidopsis thaliana Leaves and Floral Tissues

Abstract

Fusarium graminearum (Fg) is the causal agent of Fusarium head blight disease of wheat (Triticum aestivum), oats (Avena sativa) and barley (Hordeum vulgare), which targets the floral tissues and thereby adversely impacts grain yield and quality. Mycotoxins produced by F. graminearum further limit the consumability of infected grain. In the laboratory, F. graminearum also has the ability to colonize both leaves and inflorescence tissues of Arabidopsis thaliana. The interaction between A. thaliana and F. graminearum makes available a large array of genetic and molecular tools to study the interaction between plants and F. graminearum to elucidate plant genes and pathways that contribute to resistance, as well as study how the fungus targets plant genes and mechanisms to promote disease. The methods described below allow for efficient infection of Arabidopsis leaves and inflorescence, and evaluation of disease progress and fungal growth. Disease spread in Arabidopsis can be readily monitored by the visual observations of chlorosis of leaf tissue and disease phenotype of inflorescence tissue including fungal mass on surface of the inflorescence tissue. Fungal growth can be further monitored by measuring the relative amount of Fg DNA in the host tissue by polymerase chain reaction (PCR) and quantitative real-time PCR (qPCR).