Cut and dried case for early maturing rape Earliness of maturity is increasingly important in oilseed rape, allowing growers to spread workload and cash flow, release storage space, and tackle black-grass ahead of drilling wheat. But finding a “decent” earlymaturing variety hasn’t been easy until now says DLF Seeds, which is promoting Advance. A conventional variety, it matures up to seven days earlier than other varieties, meaning it can be cut, dried and sold before moving onto other crops. Breeder Mike Pickford says that, having been bred on Cotswolds brash, it’s well-suited to the British climate. “A location 900ft above sea level is very testing for a variety to be put through its paces. If it can excel here, it can do well anywhere in the UK,” he points out. Agrii seed technical specialist David Leaper believes the main advantage of growing an early variety is to provide an early entry for winter wheat, allowing growers to control black-grass through the use of stale seedbeds. Oilseed rape also uses different chemistry to cereals, so there’s an additional opportunity to prevent resistance building up, he adds. Since it uses the same machinery as cereals, an earlier harvest spreads the workload. “That also helps if
there’s limited storage. And the oilseed rape can be sold early, which helps with cash flow,” says David, who advises growers to consider the oil content of a variety as well as the yield, plus its disease profile and stem height. “When commodity prices are low, the oil content makes an important contribution to rapeseed returns. It’s worth an extra £130–£150/ha and is genetically stable, so it doesn’t fluctuate as yields may,” he points out. In AHDB candidate trials for the 2014/15 Recommended List Advance had a gross output of 104 per cent of the control, with an oil content of 46.1 per cent, higher than any other variety in RL trials. It scored an 8 for lodging resistance and stem stiffness and, being short, is easy to harvest. Earliness of flowering was an 8, allowing plenty of time for pod-fill, with earliness of maturity at 6. DLF Seeds’ David Ramdhian says: “It’s a very similar maturity to Excalibur, but stiffer and with a higher gross output.” The reason it missed out on full recommendation is because it’s so early to ripen, but all the varieties have to be harvested at the same time in the AHDB trials, he explains. “Despite this, it has a very
Earliness of flowering gives plenty of time for pods to fill.
dedicated following among growers and agronomists, and has a lot to offer on farm,” he says. Mike Pickford recommends growing Advance as a complementary variety to later alternatives. “Oilseed rape is proven to give the following wheat crop an extra 1t/ha, and there’s no other break crop that consistently produces a good gross margin. “Advance is a very grower-friendly variety. It’s uncomplicated and easy to harvest. It can be sown at a reasonable seed rate and it grows away in the autumn and spring,” he adds.
To spread the oilseed rape harvest, David Leaper suggests teaming Advance with varieties such as Exalte, Expower, Nikita or, further north, Anastasia. “They’re good vigorous autumn crops. Hybrids are also quite popular among growers looking for later crops,” he says. However, those looking to cut costs by farm-saving seed will have to avoid hybrids. For farm-saving he recommends choosing the cleanest fields, avoiding the use of glyphosate as a desiccant, using a professional seed cleaner to ensure large, vigorous seeds, and the use of a phosphate and fungicide treatment. ■
Key characters limit ﬂea beetle damage Dekalb technical specialist, Andrew Christensen.
Oilseed rape hybrids that are faster to develop before winter and earlier to commence stem elongation after winter can markedly limit damage from cabbage stem flea beetle larvae, reveals the latest research. The Dekalb study, carried out with a Cambridge breeding trial significantly affected by flea beetle, showed some of the 30+ varieties grown to the standard, untreated
protocol losing 40 per cent or more of their main stems to the pest and suffering serious stunting at flowering. In contrast, other varieties lost no stems whatsoever and showed little or no stunting. Detailed assessments of branching levels and earliness of flowering as well as main stem losses and plant stunting in early May allowed the extent of damage from flea beetle larvae to be evaluated by variety. At the same time, rating of varieties for speed of development before winter and earliness of stem elongation after winter enabled any correlations between these agronomic traits and flea beetle damage to be explored. “Contrary to popular wisdom, higher levels of main stem loss tended to result in a slight decrease rather than any increase in oilseed rape
branching,” reported Dekalb technical specialist, Andrew Christensen who undertook the study. “They also resulted in clear delays to flowering,” he added. “We recorded obvious differences between varieties too, with those developing more rapidly before winter losing markedly fewer main stems and suffering noticeably less stunting from flea beetle larvae than those developing less rapidly. The faster autumn developing varieties also tended to be better branched at flowering. “Main stem losses and stunting tended to be lower in varieties moving into stem elongation earlier after the winter than in those takingoff less rapidly,” he said. Overall, the study clearly showed varieties like DK Extrovert, DK Exalte, DK Exception and DK Exentiel, with more rapid autumn and early winter leaf growth, are better able to tolerate larval feeding from the early
winter as well as adult flea beetle damage at establishment. They were as infested with larvae as the other hybrids and the pure line control but, assisted by a greater branching ability, their extra biomass appeared to enable them to cope more effectively with the damage caused. This ability to grow away from flea beetle larvae damage appears to be enhanced by inherently earlier stem elongation – a character considered especially valuable in seasons where spring growth is badly constrained by prolonged or late cold conditions. “In addition to their role in reducing flea beetle damage, of course, rapid development before winter and early stem elongation after winter should be equally valuable characteristics in providing the greatest possible tolerance to the slug and pigeon problems that are a fact of life for most winter OSR growers,” noted Mr Christensen. ■
16 www.farmersguide.co.uk August 2016
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Published on Aug 4, 2016