WFhb1-1 plays an important role in resistance against Fusarium head blight in wheat

Fusarium head blight (FHB) is a severe disease of wheat ( Triticum aestivum L.). Qfhb1 is the most important quantitative trait locus (QTL) for FHB resistance. We previously identified wheat gene WFhb1-1 (aka WFhb1-c1 ) as a candidate for FHB resistance gene. Here we report that WFhb1-1 has been cloned. The gene (GenBank # KU304333.1) consists of a single exon, encoding a putative membrane protein of 127 amino acids. WFhb1-1 protein produced in Pichia pastoris inhibits growth of both F. graminearum and P. pastoris in culture. Western Blotting with anti- WFhb1-1 antibody revealed a significant decrease ( p < 0.01) in WFhb1-1 accumulation, 12 hours post Fusarium inoculation in non- Qfhb1 -carrier wheat but not in Qfhb1 -carrier wheat. Overexpressing WFhb1-1 in non- Qfhb1 -carrier wheat led to a significant decrease ( p < 0.01) in Fusarium -damaged rachis rate, Fusarium -diseased kernel rate and DON content in harvested kernels, while silencing WFhb1-1 in Qfhb1 -carrier wheat resulted in a significant increase ( p < 0.01) in FHB severity. Therefore, WFhb1-1 is an important FHB resistance gene with a potential antifungal function and probably a key functional component of Qfhb1 in wheat. A model regarding how WFhb1-1 functions in FHB resistance/susceptibility is hypothesized and discussed.