With autumn 2019’s challenging conditions forcing many arable growers to now consider drilling options for next year, the latest varieties of spring oilseed rape could provide a real opportunity, according to Mike Farr, of breeders, DSV.

Strong prices for oilseed rape, recent developments in breeding and a greater range of varieties mean most growers could produce a profitable crop with some distinct advantages over winter-sown options, he argued.

“Spring oilseed rape generally only requires around 150 days to grow, so phoma isn’t a problem due to its short vegetative stage and specific temperature requirements. The occurrence of fungal diseases is much less than in winter rape, so disease control is rarely necessary and drilling spring oilseed rape at the end of March/early April means less pressure is put on both man and machinery.

“Good modern hybrid varieties are tolerant of colder conditions allowing earlier drilling so crops can establish well before flea beetles become active. Growers should try and resist the temptation to drill too early, however, as temperature and day length will act against the newly sown seedling," he pointed out.

Modern hybrids, such as Lagonda and Lumen, have done much to improve establishment and the economics of growing spring oilseed rape, he added. “Lagonda marks a particular step forward in yield and vigour with a yield of 117% of control and an oil content of 44.5% in the AHDB Spring oilseed rape Descriptive List for 2019. Trials have shown it to have excellent spring vigour, so it quickly grows away from any possible pest attack.

“At 135cm, it sits in the middle of the pack when it comes to plant height and with a strong score for standing ability of 8, plus Lagonda is early to flower and has a medium maturity.”

Another contender, Lumen, sits at 106% of control with an oil content of 45%. “It’s another high vigour variety, quickly establishing a strong rooting system with early leaf set helping to ensure maximum plant survival against potential flea beetle attack," said Mr Farr.

“It is also relatively short at 138cm with excellent stem characteristics and very early maturity, which is beneficial when aiming to get the crop harvested before a change in weather conditions.”

Target drilling rate for spring oilseed rape is around 70 seeds per m2 with the aim of achieving a plant population of around 55-65 plants per m2 , but growers should be prepared to increase this on questionable seedbeds and heavy or brashy ground, he said.

“Historically, when spring oilseed rape could only safely be drilled towards the start of summer, it was one of the few crops flowering when the flea beetle were at their destructive worst. This certainly does not have to be the case now, with modern genetics making the crop a more viable and durable crop than ever.”

At harvest, the temptation to desiccate/swath early must be avoided otherwise full oil content of the seed will not be achieved, he said. “The crop will be ready when 90% of the seed in the mid-third of pods on the main stem are red to dark brown."

DSV adds to winter offering

Both DSV's winter varieties on the RL, Darling and Dazzler, have been developed for low maintenance production.

With a focus on agronomic functionality and low-input production, Darling and Dazzler are DSV’s first ever ‘triple-layered’ oilseed rape varieties to join the List, said the company’s Sarah Hawthorne.

“Joining the 2020/21 AHDB Recommended List for the East/West region, the varieties combine high gross outputs with turnip yellows virus (TuYV), RLM7+ phoma stem canker and pod shatter resistances to deliver simple maintenance and low growing costs. Both have been developed in response to the demands faced by growers, in particular the need for lower cost management and to address the impact of reduced agrochemical availability in the future," she said.

“They are designed to deliver sustained early vigour in the field to grow through pest and disease attacked whilst exhibiting a range of features that support them from canopy development through to harvest.”

Both varieties score 8 for phoma stem canker and 6 for light leaf spot resistances with one of the main features shown in AHDB trials being their consistency of yield production. Darling has a gross output 103% and Dazzler 104% with gross outputs consistently at or over 100% of control over the last three very different growing years.

Another DSV variety, Crocodile CR, is the highest yielding clubroot resistant oilseed rape to join the AHDB Recommended List by a significant margin, added Mr Farr. “With a seed yield of 106% of control in the 2020/21 RL, it is right up there with the best mainstream hybrid oilseed rapes in terms of outright performance," he said.

Clubroot spread is being driven by the tighter arable rotations used by growers in recent years, an increasing number of large mixed farming operations and greater use of brassica elements in cover crops, he explained. “This year, saw a 20% increase in plantings of clubroot resistant varieties over 2018 and this rate of increase is likely to continue over the next few years."

In this respect, Crocodile is a game-changer, he added and as well as its yield advantage, it’s got the same 45-day rapid establishment period of many DSV top performers and is also quick to get going in the spring.