Scald

Net blotch (Pyreophora teres) is a common disease of autumn sown barley (much less commonly spring sown barley) which can result in significant yield loss if not controlled. Charateristics net type lesions give the disease its common name but lesions can also take the form of dark stripes and streaks and when infection is severe in large dead areas of leaf. Infection sources are either seed or crop debris, which is borne out by second year barley crops being likely to carry infection. Net blotch development is favoured by cool, moist conditions.

Leaf rust (also known as brown rust) is a disease of barley. Whilst occurring less frequently than leaf rust in wheat it can result in significant yield loss if not controlled. Leaf rust is favoured by warmer, drier conditions with the initial source of inoculum being infected volunteer cereals. Under favourable conditions leaf rust can develop very quickly. Spores are scattered at random on the leaf and are often surrounded by a pale chlorotic halo.

Spot blotch (Cochiobolus sativus) is an uncommon expression of net blotch, a common disease of autumn sown barley (much less commonly spring sown barley). Spot blotch lesions are dark-brown and elliptical in shape.

Ramularia leaf spot (Ramularia collo-cygni) is a common disease of barley which can result in significant yield loss if not controlled. While both winter and spring planted barley can be affected, the impact of Ramularia is usually greater on winter planted crops. Ramularia is seed borne and once the fungus has infected the plant it grows within the plant, not producing visible symptoms until around ear emergence. Symptoms consist of small brown lesions which under the right conditions can rapidly increase and coalesce together.