Secrets to enhancing oilseed rape yield and quality and strategies for coping with this year’s big crop were the focus of the first 2016 meeting of the Syngenta grower’s discussion group.
Held at the ADM oilseed rape processing factory in Erith, Kent, James Southgate, field manager at Syngenta, said achieving maximum light interception was key to getting the best yield.
Growers who planted early had seen their oilseed rape rocket off the blocks and these crops were now exceptionally big. Even later-drilled crops look like normal August-drilled ones.
Mr Southgate said: “Strategic management of this year’s potentially big oilseed rape canopies could make all the difference.”
“The growing points are already well extended, as the days become longer the crop will start growing even if the weather is colder.
“If it remains relatively mild, it will start to romp away creating tall main racemes and thick canopies which will start to shade lower leaves,” he said.
Thick pod canopies may look productive, but are more prone to lodging and disease, growers agreed.
Mr Southgate said a timely application at stem extension of a fungicide, such as Toprex (paclobutrazol and difenoconazole), which has plant growth regulator (PGR) activity helps reduce canopy size in addition to synchronising delayed flowering and shortening the main raceme.
Potential benefits of synchronising flowering also came under discussion. Minimising sunlight reflectance by the flowers allows more light to be absorbed by green leaves, encouraging uniform development and maturing of pods.
“If you narrow the flowering window you are bringing your side branches into bud at the same time as your main raceme. Early application when the plant is smaller has the greatest effect as the plant is still compact.”
However, he said, the product was a fungicide, so would give protection against pests such as light leaf spot.
“If crops are at high risk for light leaf spot or the disease is already present you need to control it very early in the spring rather than wait.”
Flea beetle pressure had varied greatly across the country, with many areas reporting wide year-on-year differences.
Some areas which had been under heavy pressure in 2014 had not seen a repeat this year. Other growers who had not experienced high damage levels last season had seen greater pressure this year.
Some growers had variation within fields, with the pest moving across parts of the crop.
Mr Southgate said: “Damage appears to have occurred in pockets, but the derogation to use neonicotinoids in certain areas has helped.”
Following a no-till regime can help avoid peaks and troughs of growing crops such as oilseed rape, said Nuffield scholar Russell McKenzie, who has just finished a study on the subject.
Recent trips to New Zealand, Australia, USA, Brazil and Argentina to look at no-till systems had showed the system to be effective under both wet and dry conditions, with better water infiltration, no pooling and improved water retention during dry spells giving plants up to 10 days longer before soil moisture levels fell into deficit.
Rotations and residue retention were key areas included in his study.
Mr McKenzie said: “The carbon:nitrogen ratio in the rotation is something growers really need to take into account.
“For optimum break-down of residues the ratio needs to be 24:1, so crops such as peas (25:1) decompose relatively quickly leaving little excess. The ratio for oilseed rape is just a little higher than peas, so it fits well in a rotation.
“Wheat [80:1] has more than three times as much carbon [C] as peas and therefore needs much more nitrogen [N] to break down.”
As a result, two wheat crops in succession are likely to lock up the N, making it unavailable for subsequent cultivations.
Oilseed rape is sensitive to compaction as it can be a lazy rooting crop. Compaction can be dealt with in a number of ways, including some form of sub-surface cultivation for an instant fix or use of robust cover crops.
For some growers, volunteer oilseed rape serves as a simple cover crop.
Mr McKenzie said: “Rather than spraying OSR volunteers off early, they can be a useful option between OSR and wheat as a short-term, low cost cover crop, as long as moisture is not limiting.
“We need to be mindful not to think of no-till as being only about the machine, it needs to include details, such as balanced rotations, retaining residues and replacing cultivation techniques with cover crops.
“Improving organic matter is central to soil resilience. No-tilling on heavy soils can be more challenging, but with the right mindset it can be done, and done well.
“Results from a move to a no-till system can take time, so growers need to be patient while the soil builds organic matter and gradually become more resilient.”
To read Mr McKenzie’s full Nuffield Scholarship report go to: www.nuffieldscholar.org/news/russell-mckenzie-report-published-/
PROCESSORS were looking for consistency in the oilseed rape coming in to the factory, said Martin Farrow, general manager at ADM Oilseed Processing.
The busy site at ADM Erith, near Dartford, Kent, receives some 150 daily truckloads which it processes into refined oil for food ingredients and biodiesel.
Initially constructed in 1908 for processing oilseeds and making margarine, the factory is situated close to the M25 and backs on to the River Thames.
This made it well-placed for both seed suppliers and oil demand, said Mr Farrow, who was keen to build closer relations with farmers supplying the factory to bring both ends of the supply chain closer together.
Some of the oil refined for the food industry is LEAF Marque certified and supplies some of the best-known food producers such as Hellman’s, and carries a healthy premium to the farmer for the additional workload.
*Normal oilseed rape varieties have about 2% erucic acid, whereas the HEAR varieties, which are used for lubricants and plastics, have about 50%
iOSR is a new initiative from Syngenta, published exclusively by Arable Farming magazine, to give growers and agronomists a deeper insight into oilseed rape production.
It will combine expertise from across the industry, with in-field science from Syngenta innovation centres and the practical experiences of a group of successful growers aiming to deliver timely information and intelligence to enable more informed decisions for crop agronomy.
To read more about the project and hear from some of the growers involved visit: www.fginsight.com/iOSR. In addition, you can ask Syngenta OSR questions and join iOSR discussions on Twitter by using #iOSR.
@russbmckenzie @SyngentaCropsUK nailed it. Was a very good talk #iOSR
A good reason why OSR price is low, global increase of oilseeds from 184m tonnes in 95/96 to current levels at 428
Use #iOSR to join the discussion