Farm Ireland

Tuesday 20 March 2018

Septoria poses the primary threat as conditions promote spread of disease

Gerry Bird

The weather has been the dominant influence on tillage farms over the last number of weeks, with spraying particularly disrupted.

The T1 fungicide applications on wheat were delayed or applied in less than ideal conditions. It remains to be seen how successful they were.

Septoria is the main threat and weather conditions at present are suitable for spreading the disease from leaf to leaf.

The benefit of a T0 fungicide could be realised this season, as some of my growers did not get to apply the T1 until May.

The sight of waterlogged tramlines is a bit depressing at this time of the year and will only deteriorate with more passes. I have noticed in the past higher disease levels in tramlines where muck was thrown up on the crop, due to poorer fungicide coverage. Damaged tramlines also lead to problems with soil compaction and water percolation through the soil.

Wheat crops will have received the bulk of the nitrogen application at this stage and weather conditions from now on will be critical to maximise green leaf area. The performance of the SDHI fungicide group will be interesting this season with good crop structures and potentially high disease pressure. The full disease spectrum was present on wheat at the T1 application, owing to a combination of weather and the wide range of varieties drilled and will provide a good test of the fungicide programmes.

The dry conditions in March have increased the levels of take-all in wheat and barley in susceptible crop rotations and as crops grow on, the typical stunted crop symptoms with yellow leaf tipping become more noticeable. The application of a foliar nutrient (N&P) and strobilurine fungicide could be beneficial, but future weather will dictate how severe the infection will be.

Winter barley crops are at awns appearing stage and are relatively disease free, with growers planning to apply the next fungicide. Ramularia protection should be considered on this application.

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Winter oat crops will have received recent growth regulation and mildew control, with some showing the effects of spray damage with leaves tinged purple.

Winter oilseed rape crops seem to be flowering since early March and many crops are in full flower. The recent heavy rain and wind have lodged and tossed some crops, particularly where organic manures had been applied.

These crops were obviously tall and had made very good early season growth, and were not subject to the normal pigeon 'growth regulation' over the winter. The crops are lying over with no stem breakage and are making attempts to get upright again. However, this will only be a partial success.

Growers have been spraying to control sclerotinia, a fungus which attacks the stem and causes premature plant death, but the bulk of the fungicide applications will be made at petal fall to control leaf spot.

Spring barley crops are growing well, with top dressing completed and herbicide applications next on the list in my area. Grass weed will be an issue on some of the heavier soils and crops after grass. The excellent sowing conditions are very much in evidence, with crops tillering well and virtually no pest damage to report.

Spring oilseed rape was quite slow in emerging, but crops are progressing now with most at the 2-4 true-leaf stage.

The novel camelina crop had a very slow emergence but is now at the 6-8 true-leaf stage. Slug damage has been reported on some crops, which was brought to our attention in the husbandry programme.

I mentioned the Tellus project last August, and it is now coming to an end. The project team sampled the soils and stream sediments for a wide range of minerals on the border counties from Donegal to Louth. The samples will be analysed and the data will be available.

Check out the GSI website,

Gerry Bird, is crop consultant and member of the ITCA and operates from Co Meath. Email:

Indo Farming