14.5 Pathogens that produce haustoria (Ascomycota and Basidiomycota)

Flax rust (Melampsora lini, Basidiomycota) and barley powdery mildew (Blumeria graminis (also known as Erysiphe graminis), Ascomycota), share the ability to produce specialised feeding structures called haustoria that penetrate the living cells of their host plant. This gives them intimate contact with live host cell membranes through which they can extract nutrients and suppress plant defences. Smut fungi (species of Ustilago, Basidiomycota) are particularly important pathogens of cereal crops; they do not form haustoria but nevertheless make close contact with living host cells through intracellular hyphae that invaginate the host cell membrane.

All of these pathogens are of major importance to agriculture and comparison of the ways in which they interact with their hosts in terms of cross-recognition and cross-signalling, and the virulence and resistance genes involved in these interactions is seen as a way of improving understanding of the biology of their relationships with their host plants and a way to improve food production (Ellis, Dodds & Lawrence, 2007).

Resources Box

More information about plant pathogens

More information about plant pathogens can be found in the British Society of Plant Pathology’s Pathogen profiles, which are a regular feature in the journal Molecular Plant Pathology and BSPPWeb providing brief overviews of the latest research on particular pathogens.

Profile summaries are available at http://www.bspp.org.uk/ [go to <Publications> and then click on <Molecular Pl. Pathology>]
Full articles can be downloaded from the Blackwell Molecular Plant Pathology web site [http://www.blackwellpublishing.com/journal.asp?ref=1464-6722&site=1]

We would also strongly recommend a visit to the teaching materials on the website maintained by the Department of Plant Pathology of the University of Wisconsin-Madison, USA at this URL:


Updated December 17, 2016