The T1 fungicide is the first big fungicide spray on winter wheat.

It’s essential in trying to prevent Septoria from getting out of hand in winter wheat and should be targeted at the third last leaf.

It needs to hit leaf 3 and protect it.

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It will also provide protection for leaf 2 which will be emerging. The goal is to keep the top three leaves as green as possible to maximise photosynthesis.

For some crops it will be their first fungicide spray and so needs to be applied in a timely manner.

Graham winter wheat with leaf 3 emerged.

For others, it may be the second. However, T0 fungicides are generally focused on rust control, but the multisite component will help to keep Septoria at bay.

To get the timing right for the T1 you will need to take the plant apart. Strip back the leaves, place them in order and count back from the small flag leaf to leaf 3 – see images.

The plant needs to be taken apart to count back the leaves.

If leaf 3 is the leaf that is fully out, it is time to spray, but really growers should be keeping an eye on the leaves emerging so they spray on time or ahead of bad weather.

Leaf 3 emerged is the target, but as we all know the weather may not allow the crop to be sprayed.

In the current cold weather crops will not grow too fast, but the growth stages are easily missed. The T2 should be applied to the flag leaf, the last leaf. The T3 should be applied at flowering.

Products

Folpet should be applied at both T1 and T2. You should not apply the same methods of chemistry at T1 and T2. Products should be mixed and alternated to try and prevent resistance.

Cold temperatures are probably helping to keep Septoria at lower levels at present, but given the chance Septoria will burst into crops in damp and warm conditions.

Prevention is better than cure, because we are limited on curativity. It is not really an option.

Ascra and Revysol are good options for T1 at present with an Inatreq based product at T2.

If your agronomist is concerned about septoria they may got for the Inatreq product at T1. Inatreq can only be applied once in the season. The key is to mix it up and switch products.

Graham winter wheat leaf 3 emerged.

Make sure crops are well fed, deficiencies are looked after and carry out a leaf analysis test if you think there is an issue in the field. A healthy crop will fight disease better. If rust is present, add a strobilurin or tebuconazole.

If you used tebuconazole at T0 you should not use it or Revysol at T1. If you used prothioconazole at T0 you should not use prothioconazole at T1.

Graham winter wheat leaf 3 emerged.