Net Blotch

Pyreophora teres
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.
Net Blotch

There are two types of net blotch differentiated by the symptoms: a net form and a spot form. Both occur in NZ but the net form is more common.

Look out for:

  • Net like symptoms, especially in 2nd year barley crops

Risk Factors:

  • Infected stubble or seed
  • Cool, moist conditions

Infection can be seed borne or from infected stubble.

Net blotch favours cool, moist conditions.

Yield losses of 10-30% have been recorded.

Related Pests