Crop Clinic

The key time to control the disease with fungicides is in the spring up to GS32. Failure to control the disease at this time can lead to a loss in yield and quality at harvest, particularly where the disease weakens the stem base and causes the crop to lodge.

This leads on to ask how do you know if your crop is at risk from eyespot? If you find lots of the diseases in the crop when you look now the decision is easy but it’s rare to see eyespot causing very visible symptoms this early and therefore very hard to spot at risk fields this way. SAC has been working on a model to determine the risk of eyespot in crops with HGCA funding.

The work disproved some very common misconceptions about eyespot. Minimum tillage far from encouraging this trash borne disease actually reduces the risk, and incorporating the straw also reduces the risk by a small amount when compared to baling and removing it. Amongst the biggest influences were previous cropping, the presence of eyespot and tillage. Rainfall  during the winter and spring was also important, with higher risks found in the north and west. Sow date and soil type also had an influence on eyespot risk.  We found however, that the varietal resistance rating for eyespot made no difference .

Eyespot Accumulated Risk Score

To determine the risk of eyespot developing in a crop to levels that will be economically damaging, calculate an accumulated risk score from the table below.