RNA-Seq Revealed Differences in Transcriptomes between 3ADON and 15ADON Populations of Fusarium graminearum. Fusarium graminearum

Fusarium graminearum is the major causal agent of Fusarium head blight (FHB) in North America and other regions of the world. The pathogen causes direct yield losses and produces various types of trichothecenes mycotoxins [Deoxynivalenol (DON) and its acetylated forms (3-acetyl-4-deoxynivalenol=3ADON and 15-acetyl-4-deoxvevalenol=15ADON), nivalenol (NIV). Recent studies indicated that 3ADON-type isolates were significantly increased in North America and China in recent years and appears to be more aggressive based on growth rate, disease severity on different cultivars, and DON production in vitro. Thus the overall objective of this this study was to understand the molecular mechanisms that make 3ADON- and 15ADON-type populations different during infection using a susceptible cultivar, and to compare the transcriptomes of the 3ADON- and 15ADON-type populations in vitro and in planta using the RNA-seq approach as well as to identify the expression differences of candidate genes related to aggressiveness and DON production. Overall design: Experimental samples were collected from in-vitro and in-planta inoculations with Fusarium graminearum isolates producing different mycotoxin derivatives. In in-vitro, Mung Bean Media was inoculated with a mix of 10 isolates of either 3ADON or 15ADON isolate population, incubated for five days and harvested to extract RNA. While for in planta, a susceptible spring wheat cultivar- Briggs was point inoculated at the flowering stage by both populations separately. The samples were collected at 48, 96 and 144 hours after plant inoculation. In both cases, samples were flash frozen in liquid nitrogen and ground to power for RNA extraction using Promega SV total RNA isolation kit. Extracted RNA was converted dscDNA and used for library preparation and sequencing using TruSeq RNA sample preparation kit from Illumina.