West: Septoria strategies have proved successful

As Wimbledon approaches it signals a critical time. Sunshine is vitally important for both the smooth running of a tennis tournament and for good yields in crops, with good sunlight levels needed for crops to fulfil their potential and tennis players to complete their matches.

Wheat crops are holding onto green leaf area quite well. As we always get septoria in the west, it’s not a case if the disease takes out leaf area, but when. Each day we can prolong green leaf area contributes 0.2t/ha in dry matter. Septoria control strategies have worked well, but we are starting to see small septoria lesions on leaf 2 and the tip of the flag leaf, especially where T2 was delayed due to the windy conditions. If our flag leaf sprays hold it to that level then they will have done well!

Flowering has started on earlier sown wheat crops as I write this, so T3 decisions have been made. Crop prices have influenced these decisions, as fusarium control is often down to luck of timing sprays close to rainfall infection events at flowering. In addition, all products only claim suppression, so I have based sprays around the cost effective tebuconazole, choosing co-forms with prochloraz or prothioconazole where I felt extra septoria or mildew top-up was required.

Winter barley crops are holding up quite well both in terms of disease control and standing up in the recent unseasonable strong winds. These have been testing the plant growth regulator (PGR) input, although generally crops are not too tall, so I was fairly confident they would stand without the need for late PGR. I hope won’t be proved wrong.

I still stand by my prediction that barley yields will not stand out this season due to thinner than optimum crops. I have fewer hybrid barley crops than last season and they look to have better potential. I think they do offer advantages in yield and earliness over 2 row varieties, so let’s hope the talk that seed costs will come more in line will make them look more attractive as we think about cropping plans.

Growth pattern in oats has been strange this season and the usual burst of stem extension growth has been delayed. Many crops are short and the later dose of Canopy (mepiquat + prohexadione) I planned to use has not been required. Disease levels have been low, but I have still continued with a second fungicide as panicles emerge as it protects against late crown rust developing and helps keep the sample bright.

Spring cereal growth slowed in the cooler temperatures of a few weeks ago, but they have picked up recently. Early weed control, growth regulation and fungicide inputs have all worked well. Flag leaves are now out or emerging, so T2 recommendations have been made.

Maize crops have finally picked up as well with the recent rise in temperatures. Pre-emergence herbicides have worked well, but there is enough troublesome weeds for post-emergence contact herbicides to be necessary and now the crop growth has improved, I am happier that we will not scorch them too much.

Spring beans are now starting to flower and losing their chlorosis from the pre-emergence herbicides. Weed control has been variable, but I have only resorted to bentazone on the worst fields. Despite temperatures only recently improving, I have found crops with black bean aphids, so have had to treat with pirimicarb.

I am converted to the use of foliar phosphites on this crop to protect against downy mildew and promote early crop health, but the press reports of farmers being penalised by inspectors due to the application contravening the crop nitrogen requirement (or lack of it!) for the crop, I can’t help feeling that the rules in the book are being used without full understanding. The low levels of foliar absorbed nitrogen in these products which is necessary for formulation reasons surely does not pose any environmental risk and if it removes the need for a pesticide application, it is beneficial.

So as we close in on the summer solstice let’s hope the forecast I’ve just seen for the rest of June – to be more dominated by high pressure – is correct so that we get bright, sunny, cool, but not hot conditions required for grain filling and, therefore, good performance from crops. That’s going to be critical to our clients with current commodity prices.

Maybe it will also induce some outstanding home grown performance on the courts of Wimbledon or even the Ashes test matches – I am an eternal optimist!

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