The pathogens confirmed included Eyespot (Aureobasidium zeae), Common Corn Rust (Puccinia sorghi), Northern Corn Leaf Spot (Bipolaris zeicola) and Alternaria. The most commonly found disease was Eyespot.

Pictured on this site are some of the leaves sampled. The pictures show the symptoms of specific infections and combinations of different infections - and also close up views of each disease identified.

Maize is vulnerable to infection by certain plant pathogens throughout the growing season and particularly under favourable environmental conditions. Many of the pathogens that cause the diseases identified in 2008 survive in crop residue left on the soil surface leading to increased levels of disease when maize follows maize. Moderate temperatures, high rainfall and dull conditions during the growing season will also significantly impact disease severity.

It is probably no coincidence that the increased disease levels experienced in the UK & Ireland are correlated with the wet, cool and dull summers of 2007 and 2008. Under moist conditions the fungi responsible for the infection produce spores that are either rain splashed or wind blown onto susceptible crops. As the season progresses the infection moves from the lower canopy to the upper canopy.

Generally if foliar diseases do not become established until well after tasselling yield losses are minimal. If disease becomes established before tasselling or within three weeks of tasselling yield losses may occur.

Where possible, avoid growing maize after maize and ensure that stubbles are ploughed to reduce the chance of cross infection to the next season. Avoid min-till practices where practical.

A Single Off-Label Approval has been granted in the UK (MAPP Number 13022) and in The Republic of Ireland for the use of flusilazole on forage maize to control Eyespot.

Pioneer is currently assessing all the hybrids it markets in the UK with regard to their disease resistance to the various pathogens highlighted above. For specific advice about reducing disease infection in your maize crop please contact your Pioneer Agent or Pioneer directly using the contact details on this website.