Timing of T2 Fungicide is Critical - Elle Pace - South East Farmer

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- South East Farmer

According to Elle Pace, Hutchinsons agronomist in Hampshire, Sussex and Surrey, most winter wheat in the region is looking forward. She observes that early drilled wheats have enjoyed a mild winter with very few frosts as yet and are looking forward and lush. The later drilled wheats have also kept growing through the winter. Generally, wheat crops are looking good with some Septoria and some mildew evident.

Elle Pace

Farmers must make sure that they get their T2 spray on at the right time. This treatment is by far the most important and gives the largest yield response out of the whole programme. It aims at protecting the top two leaves which are themselves responsible for two-thirds of the total yield. Normally T2 is applied around mid to late May, Growth Stages 37-39, and within three to four weeks of the T1 application. Timing is critical and the T2 treatment usually takes the form of a combination of an SDHI and a strong triazole such as epoxiconazole or prothioconazole. The SDHI provides some curative activity which will probably be needed at that time.

Elle also warns growers of the risk of fungicide resistance and hence the importance of using any fungicide according to its label restrictions in terms of maximum numbers of sprays and of using fungicides with different modes of action as part of an anti-resistance strategy. She says that the T2 treatment aims to protect the plant against Septoria, which is likely to be the main target disease, and also against rusts. Often which rust, ie yellow or brown, depends on the variety as well as the weather conditions. A lot of the Group 1 wheat variety Crusoe is grown in the South East and this produces very good yields but has a low rating for brown rust (just 3). Elle says you need to bear the variety's disease rating in mind to make sure you plan the right fungicide combination.

Of course, disease development will be heavily influenced by weather conditions and it is too early at the time of writing to predict the disease pressure we may suffer this season.