IBH Seminar: Genetics of Fusarium Head Blight Resistance in Barley

When: Thu, 17 Oct 2024 15:00 – 16:30 BST

The International Barley Hub is pleased to announce the next in the 2024 series of seminars: ‘Genetics of Fusarium Head Blight Resistance in Barley’ presented by Brian Steffenson and Ahmad Sallam (Department of Plant Pathology, University of Minnesota)

Speakers bio:

Brian Steffenson

Brian received his B.S. and M.S. degrees in Plant Pathology at the University of Minnesota in 1980 and 1983, respectively. He then worked for several months as a research associate at the Waite Institute/South Australian Department of Agriculture and at the Plant Breeding Institute of the University of Sydney in Australia. He earned his Ph.D. in Plant Pathology at the University of California-Davis in 1988 and then accepted an assistant professorship at North Dakota State University with research responsibilities on foliar and head diseases of barley. In 2000, Brian accepted a professorship as the Lieberman-Okinow Endowed Chair of Cereal Disease Resistance at the University of Minnesota in St. Paul. Brian’s main research interests include breeding cereal crops for disease resistance with genes derived from wild progenitor species, virulence and molecular diversity of fungal pathogens, and host-parasite genetics.

Ahmad Sallam

Ahmad received his B.S., M.S., and Ph.D. degrees in Plant Breeding and Quantitative Genetics from the Department of Agronomy and Plant Genetics at the University of Minnesota in 2002, 2005, and 2014, respectively. Then he started working as a postdoc in the Steffenson lab at the Department of Plant Pathology in the University of Minnesota, where his research focused on the identification of novel stem and leaf rust genes in barley and wheat. Currently, he is a senior research scientist working on exploring genetic diversity and developing germplasm for winter survival and disease resistance in small grains. He is leading the winter durum wheat breeding program for developing durum varieties with improved yield, quality, and disease resistance under the Minnesota winter growing conditions.

Summary:

Fusarium head blight (FHB) is one of the most devastating diseases of barley because it can severely reduce the yield and quality of the grain produced and also contaminate it with mycotoxins. It is caused by a number of different Fusarium species which can produce various mycotoxins hazardous to humans and animals. Over the past few decades, the disease has become more widespread and severe in many cereal-producing regions of the world. Management of FHB and its associated mycotoxins is very difficult, requiring an integrated strategy of various management practices, fungicide application, and the use of resistant cultivars. More than 25,000 accessions of Hordeum vulgare have been evaluated for their reaction to FHB in the field, but unfortunately none exhibited a high level of resistance. Mapping studies were conducted with accessions possessing partial resistance to identify the number, chromosomal position and allelic effect of quantitative trait loci (QTL) contributing to FHB resistance and DON accumulation. A meta-analysis based on a new consensus map revealed 96 QTL for FHB resistance and 57 for DON accumulation scattered across the barley genome. Many of the QTL explained a low percentage (<10%) of variation for the traits and were often found significant in only one or a few environments in multi-year/multi-location field trials. Moreover, many of the FHB/DON QTL mapped to chromosomal positions coinciding with various agro-morphological traits that may influence the level of disease (e.g. heading date, height, spike density, and spike angle), raising the important question of whether the former are true resistance factors or are simply the result of pleiotropy with the latter. Considering the magnitude of effect, consistency of detection across environments and independence from agro-morphological traits, only a few QTLs for FHB/DON were considered priority targets for breeding. In spite of the challenge for having a limited number of useful QTL for breeding, genomic selection holds promise for increasing the efficiency of developing FHB-resistant barley cultivars. Indeed, several breeding lines with markedly lower disease severity levels than older standard cultivars were identified in the Minnesota barley breeding program and are slated for release in the near future.