How to turn crop potential into profit this June and July

Crop Progress

Wheat flag leaf sprays were applied from the middle of May in the southwest. Septoria pressure, particularly in early drilled crops, has been high, although T1s look to have done a decent job in a tough situation.

Later drilled wheats – anything from late October onwards – look pretty good with disease remaining at the base of the crop. At the time of writing in May it hadn’t migrated up the plant.

A combination of a mostly mild winter, lack of spray days, no insecticidal seed treatments, and a conscious decision by some growers to not apply insecticides has contributed to barley yellow dwarf virus showing in patches in some fields.

Some oilseed rape crops continued to flower well into May. There have been noticeable differences between varieties in flowering duration and timing. With rain during flowering, petals are lying in plant axils, contributing to Sclerotinia risk.

Matt’s agronomy tips for June

1)      Target Fusarium and foliar disease top up with ear sprays

Wheat crops aren’t short of water so if sun comes at the right time will have a decent amount of potential. That should make it worthwhile to continue protecting from diseases with an ear spray.

Where growers have used a non-SDHI treatment at either T1 or T2 – for example, Univoq (fenpicoxamid + prothioconazole) – and still have one of their two permitted SDHI treatments available to use, then there’s the potential to use Aviator (bixafen + prothioconazole) at T3.

Aviator will help both with a Septoria top up and cover Fusarium. It will also control either yellow or brown rust if the weather warms and those diseases finally emerge this season. There’s no point in keeping Septoria under control all season, only to let rust run away and lose yield at the end.

Using a SDHI fungicide at T3 will also contribute to physiological greening, a bit of extra nitrogen scavenging and stem strengthening.

A rate of 0.75 L/ha of Aviator should cover all those diseases, albeit maybe with a top up of some tebuconazole or prothioconazole where Fusarium is a threat. Aim for mid-flowering when the ear spikelets are more open to help get the fungicide into ear.

2)      Careful timing for OSR desiccation will pay off

As with most applications, timing is crucial with oilseed rape desiccation. Going too early can cost yield, oil content and leave the crop at risk from red seeds and potential rejection.

We have a good crib sheet on our website to help with visual assessment of when the crop is at the correct timing. The aim is for the crop to be below 30% moisture content – going too early you can end up with red seeds and rejections, as well as a lower yield and oil content.

When sampling try to take a representative sample of the field from main racemes with pods from both upper and lower parts of the canopy. When at least two-thirds of the seeds have turned from green to brown in 15 of the 20 pods sampled the earliest correct timing for glyphosate application has been reached.

Rate will depend on whether you are also targeting weeds, and what those weeds are, but for just harvest management around 720g/ha of glyphosate should be used. If you have perennial weeds, the rate will likely need to be higher.

It’s worth using a premium Roundup brand for this application – our trials show it is 10-15% more effective and will work more quickly too, which is important at harvest. Remember there is a 14 day statutory interval between application and harvest.

3)      Select oilseed rape varieties for next season

June is a good month to visit various trials days and events to start looking at variety choice for next season.

For oilseed rape in the south, good autumn vigour is likely to be at the top of many growers’ requirements. Look for a variety that is tolerant of the sometimes difficult conditions at planting and can therefore get away from flea beetle damage to give a good autumn crop architecture to help weather the winter. Good disease resistance to Phoma and light leaf spot will also help take the pressure off fungicides.

Generally our range of Dekalb varieties have all of these characteristics, as well as good standing power and pod shatter resistance. We also have varieties with turnip yellows virus resistance, which is an important trait to consider especially if you have other crops in the rotation that peach-potato aphids will be targeting. The same applies for club root and tighter rotations with brassicas.

4)      Plan potato blight programmes

It’s been a later potato planting season for many growers in the south, but crops will grow quickly in warm seedbeds. If current weather patterns continue, blight pressure is likely to be higher than last year.

We’ve got resistance to a number of actives, but not to either fluopicolide or propamocarb that are in Infinito. It’s a product that has done well in Euroblight trials, especially for tuber blight control, so it is worth planning programmes in advance and mapping out when you use Infinito, including saving one or more applications for the end of the programme.

If you’re growing a variety that is susceptible to early blight (Alternaria) – Markies being the obvious one – we also have Caligula (prothioconazole + fluopyram) available, which again has performed well in Euroblight trials. It doesn’t have any activity against late blight so needs to be built into programmes to cover that disease as well.

5)      Take care of weeds early in maize

Like potatoes, maize planting is a bit later than usual this year because of the weather. It has not been conducive to preparing seedbeds and drilling, but drier weather in the latter half of May means growers have been cracking on.

Ideally these crops will receive a robust pre-emergence to lessen weed pressure on post-emergence sprays.

If you’re particularly targeting grassweeds, MaisTer (foramsulfuron + iodosulfuron) is a good choice post-emergence. It has received four out of four stars in Maize Growers Association trials for grassweed control, higher than some of the more established actives like nicosulfuron. There are some fields potentially where there are weeds with reduced sensitivity to active ingredients so it’s worth rotating actives within maize as well.

While MaisTer has a wide spectrum, it is weaker against black bindweed and fumitory. Mixing it with 0.75 L/ha Callisto (mesotrione), as well as Mero rapeseed oil, will help plug those gaps.

Where you have rapidly growing maize and hot weather conditions, take care with applications to avoid scorch. Spraying in early mornings or late evenings when the heat of the day has diminished will reduce risk.

6)      Visit a Bayer Field Day

While we don’t have a Bayer Field Days site in the south west, for some in the region our trials sites at either Callow, Hereford or Hinton Waldrist, Oxfordshire might be within range.

Both will have a wide range of wheat varieties untreated and treated to view, plus various other fungicide programmes including a look at how our new active ingredient Iblon compared with current market standards.

Click here to request a FieldView Demo