Using live cell-imaging techniques we have been investigating the infection of barley leaves by the fungus Rhynchosporium secalis. Commonly known as 'scald' or 'leaf blotch', this is one of the most important diseases affecting barley (see the Rhynchosporium secalis pages). Using fluorescent probes, live cells of both the plant and the fungus are stained green, whilst cell walls and nuclei of dead or dying cells stain magenta.

Following spore germination on a susceptible barley cultivar and penetration of the cuticle, subcuticular hyphae frequently grow above anticlinal epidermal cell walls (Fig. 1, right).

When observed eight days after inoculation, in some areas an extensive hyphal network can be seen overlying epidermal cells which show some signs of disruption (Fig. 2, below left).

In other areas, the epidermal cells have collapsed leaving intact mesophyll cells in the underlying layer, and also some areas of dead hyphae (Fig. 3, below right, see chains of small magenta dots).