DSV United Kingdom Ltd.

Will the latest hybrid semi-dwarf oilseed rape variety help growers overcome some of their agronomic challenges?

Described as a breakthrough by industry commentators, Troy is one of six new varieties to join the 2013/14 HGCA Recommended List for the East/West region and one of nine added to the North region.
 
Standing out from the crowd is difficult in such circumstances. But the fact that it’s the first semi-dwarf variety to perform as well as standard height oilseed rapes has been noticed, and that’s before its management and harvest benefits have been considered as well.
 
DSV’s trials manager, John Sweatman, has grown Troy for the last three years and is quick to point out that it has a very different growth habit and physical appearance to other semi-dwarfs
 
“Most relevant to this year is the fact that Troy doesn’t exhibit any of the early sluggishness that has been reported with previous semi dwarves,” he says. “It seems to have the autumn vigour that we’ve seen with the best standard size hybrids.”
 
Getting a plant population of 35-40 plants/m² in the spring is the target, he explains, which is why this is so important. “It also helps it cope with less than optimum soil conditions, late drilling and bad weather – things which were all an issue last autumn.”
 
Two distinct phases of vigour have been observed in the field, he reports. “The first is in the autumn period, which gets the crop established and allows it to grow away from pest and pigeon damage, while the second is in the spring.” 
 
The spring ‘kick’ sees the plants growing quickly to 1.3-1.4m, advises Mr Sweatman. “It is taller than other semi-dwarves,” he acknowledges. “But the extra height does seem to give it higher yield potential.”
 
With the physical bulk or biomass, but not excessive height, Troy never gets tall enough to be unmanageable or prone to lodging, he adds. “Its compact growth habit is also a bonus when applying nitrogen or sprays, as well as making it quick and easy to harvest.”
 
Case Study  - Lodging
 
Lodging was a serious problem for Derbyshire grower Rob Holmes last year, despite reducing the amount of nitrogen he applied to his oilseed rape crop in an effort to keep it standing.
 
Familiar with oilseed rape varieties getting ahead of themselves on his good land – which tends to carry a lot of residual nitrogen - Mr Holmes has seen varieties getting too tall before. But 2012 was a real eye opener, with big name varieties suffering badly.
 
For this reason, he drilled 35acres of Troy last Autumn. “I’d looked at semi-dwarves before as a way round the problem, but wasn’t too impressed with their yield potential,” he admits.
 
As his focus is on output, Troy was considered and chosen for part of the farm’s oilseed rape area. “It appealed because it should stay standing, regardless of soil nitrogen. But in addition, its yield and gross output potential is right up there with the best. “
 
Despite the bad conditions last year, Troy established well at an even plant population of 30-35 plants/m², he reports.
 
“In a good year, it should produce returns as good as anything else, but in less than perfect conditions it should still deliver even when the others are falling over.”
 
Case Study - Harvesting
 
Standing power has become a priority for Lincolnshire grower Sam Markillie, but harvesting benefits are also high on his list of variety characteristics.
“Last year we had some issues with lodging so standing power has become more of a priority when choosing which variety to grow. But we’ve also found that combining OSR is becoming more problematic,” he says.
 
That’s because crops are often very tall, with green stems that the combines find difficult to handle, he explains. “Harvest pressure results in us raising the combine header to increase output and reduce losses so we are left with waist high stubble which is less than ideal for the following cultivations.”
 
His decision to drill 80 acres of Troy was taken before the variety had been recommended, but he was impressed by the combination of its compact growth habit and yield potential.
“A semi-dwarf should minimise harvest problems by its very nature, but the yield penalty has been too great to contemplate them until Troy came along.”
 
Establishment was even with good vigour, he reports.
 
 Case Study – Pest Problems
 
Swans are the main pest problem for Cambridgeshire oilseed rape grower Paul Hartley, who admits to having had crops decimated in previous years.
 
“They’re attracted to large plants with a lot of top,” he says. “So a smaller plant should suffer less, but until now the performance of existing semi-dwarves just hasn’t been there."
As a result, he has 50 acres of Troy in the ground. “We couldn’t get hold of it last year, which was a shame. It’s the first semi-dwarf to have the yield performance.”
 
He direct drills his oilseed rape crops into stubble, to try and deter both swans and pigeons. “Troy’s got lots of ‘get up and go’ which means it should be hardy enough to grow through early attacks by swans and pigeons.
 
“Further on we are hoping its compact growing habit will give it protection against the swans and allow it to remain standing, so we should get an easier and quicker harvest than last year.”& amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; amp; lt; /div>