Role of Wild Grasses on Initiating Leaf Blotch in Barley Crops Revealed

Scientists from Rothamsted Research in England shed light on the role of wild grasses as a source of fungal pathogens to initiate leaf blotch epidemics on barley crops. The researchers found that five very closely related species of the fungus, Rhynchosporium, are specialized to infect different wild grasses and barley, which could allow them to understand types of host resistance to diseases. The disease is spread to new areas on infected seeds and is splashed by rain short distances within barley crops. It is possible that spores could also spread into crops from ryegrass in grass margins around fields especially when a fine spray is created by heavy rain and strong wind.

The research used molecular fingerprinting, DNA sequencing, spore morphology, scanning electron microscopy and host-infection tests and to investigate which grasses and cereals were infected by different Rhynchosporium species. The project also discovered a new species of Rhynchosporium (R. olii), which was found to infect only ryegrass. Novel species-specific PCR diagnostic methods were developed to distinguish the five closely related Rhynchosporium species.

See Rothamsted Research's news release at http://www.rothamsted.ac.uk/news/disease-found-common-wild-grass-affects-barley-crops.