Two new Dekalb hybrid oilseed rape varieties are being trialled this season alongside regular oilseed rape crops. In the first of this series, Philip Case looks at establishment

Seven of our regular farmer contributors are among 50 growers trialling two new hybrid oilseed rape varieties from Monsanto’s Dekalb breeding programme.

The aim is to assess how both DK ExPower, and the low biomass variety DK Sequoia, fare when grown commercially alongside other oilseed rape crops using the same crop management.

In return, growers will provide feedback on variety performance at three key stages of the year – establishment, canopy development and crop condition.

Farmers Weekly will be following the progress of our seven Farmer Focus and Barometer Farmers taking part in the comparison, providing a warts-and-all record. All have chosen to trial DK ExPower.

Both DK ExPower and DK Sequoia are candidates in this season’s Recommended List trials. DK ExPower has a gross output of 104% of the controls, with 9 rating for stem canker resistance and 8 for light leaf spot.

DK Sequoia is a low biomass hybrid which is capable of outyielding Excalibur with a gross output 103.8%. A late drilling variety, it has minimal lodging and 6 for stem canker resistance.

Generally, the autumn is proving ideal for establishing oilseed rape crops, although increased numbers of cereal volunteers and blackgrass will test herbicide programmes in the coming weeks.

Leicestershire grower and Farmer Focus writer Keith Challen is comparing his DK ExPower with Sesame, establishing it using an Autocast unit mounted on his Claas Lexion 580 combine. In total, he is growing 400ha of oilseed rape, with ES Astrid, Vision and DK Cabernet also being grown.

“My oilseed rape looks well, although we have suffered with slugs,” he says. “Crops are at the six-leaf stage and are looking healthy despite a small amount of downy mildew and leaf miner damage.”

The ExPower/Sesame comparison was drilled in a difficult spot where soils are cold and heavy and slug pressure is high, he says.

“The area is also surrounded by woodland, so the threat of pigeons is high. It should be a good test.”

The Sesame is growing more vigorously than the ExPower at this early stage, he notes.

Blackgrass is proving a challenge for Mr Challen with patches appearing in the same places as seen last season in a crop of wheat.

A dose of Roundup (glyphosate) applied to a stale seed-bed took out some blackgrass, but more have germinated since drilling. Most of the rape crops will receive an application of Aramo (tepraloxydim) in two weeks’ time, followed by Kerb (propyzamide) shortly before Christmas.

Lincolnshire grower Will Howe drilled his ExPower on 6 September and he says it is looking thin compared with other varieties.

“The rape plants that are there look strong and healthy, but it’s a bit patchy in places,” he says.

Dorset grower and Farmer Focus writer Andrew Blenkiron drilled his ExPower a week earlier.

“The ExPower looks ideal, just like the rest of the neighbouring Castille,” he says. “The crop is in a fantastic seed-bed and is germinating well.”

However, cereal volunteers are proving to be a problem this season for him. He has already taken out volunteers with Roundup applied to a stale seed-bed followed with a pre-emergence spray of 0.245 litres/ha of Centium (clomazone) and 1.5 litres/ha of Marksman (metazachlor).

He then sprayed 0.4 litres/ha of Fusilade (fluazifop-P-butyl) at the end of September when volunteers had freshened up again with cypermethrin added to the tank mix where any beetles become evident.

Fertiliser application technique

Our growers are using a variety of different techniques to apply nitrogen fertiliser this autumn and get crops off to a good start.

Mr Howe has for the first time added 20kg/ha of nitrogen in the form of di-ammonium phosphate to the seed-bed, in one pass of his TWB subsoiler seeder.

“This year I’ve decided to add my fertiliser at seeding to cut down on costs, time and help the environment,” he says.

Previously, he applied 30kg/ha of nitrogen after establishment, but found he was wasting N on parts of fields not being cropped and just fertilising weeds.

Also making the switch to seed-bed nitrogen is southern Barometer Farmer Andy Barr. At planting, 30kg/ha of nitrogen was mixed with 2 litres/ha of Maxi-phi AM1009, just in front of the seed via a Techneat spray system.

“This year is the first time we’re doing it all off the subsoiler,” he says. “Seed was dropped in 50cm rows behind the tines of a Techmagri Profilab curved leg cultivator and before the wavy disc packer.

“This was worked into spring barley stubble and followed by heavy ring rolls.”

Humberside Barometer farmer Jonathan Fenwick, however, has chosen to apply his nitrogen in a liquid form to achieve higher application rates.

“If you broadcast nitrogen you are restricted to 30kg/ha, but with the Nitrojet we have been able to apply 40 litres/ha of Omex at 17-8-0 liquid formulation (42kg/ha of nitrogen and 20kg/ha of phosphate),” he explains.

“It’s been a huge benefit and given us an amazing cost-saving on fertiliser.”