Ramularia Leaf Spot
Initial symptoms of Ramularia leaf spot (RLS) are small brown spots. These then develop into larger, reddish-brown lesions, which can have a yellow margin. RLS lesions penetrate through the leaf. Symptoms can develop very rapidly when conditions are favourable.
Look out for:
- Small, brown spots
- Larger, reddish-brown lesions
- Infected seeds
- Barley stubble
- Spring rainfall
- High light intensity following flowering
RLS has a complex life cycle starting with infected seed. (None of the available seed treatments control RLS). The disease then grows unseen within the plant before it causes symptoms, usually after barley flowers.
If trash from a previous barley crop is present spores from this source can infect a crop during the season.
Spring rainfall and also periods of high light intensity following flowering favour RLS.
Yield losses of 20% have been recorded.