The British Beet Research Organisation held its annual Winter Conference. Dominic Kilburn attended
The British Beet Research Organisation (BBRO) held its annual Winter Conference at the Peterborough Arena in early February. Dominic Kilburn attended.
Research suggests that current nitrogen recommendations for high yielding sugar beet crops are correct and that an optimum dose of 120kg N/ha, applied early in the season, will maximise the early phase of canopy expansion and enhance yields.That’s according to University of Nottingham Associate Professor in Agronomy, Dr Debbie Sparkes (left), who works on a number of collaborative projects with the BBRO.Speaking at the BBRO’s Winter Conference in early February, she said that sugar yield is directly related to the amount of light that is intercepted by the crop canopy and the more radiation that is intercepted, the higher the yield.”The key benefit of nitrogen in sugar beet is to promote early canopy expansion so that the crop can maximise light interception between May and August. Later on the crop will take up more soil mineral nitrogen but the early crop needs readily available N.”Dr Sparkes highlighted work which demonstrated that as nitrogen dose rates increased, then root yields did accordingly, however 120kg N/ha was the optimum amount, after which there was no yield benefit. In addition, she pointed out that sugar content can decline if applications rise above the optimum.
“Too much nitrogen can result in excess leafy growth and it takes the energy away from the root.”The key thing is for nitrogen to build the canopy, and 100-120kg of N/ha early in the season is needed to do this on mineral soils,” she added.Late crop N?
Continuing with the fertiliser theme, Dr Sparkes questioned whether late harvested crops needed more nitrogen to maintain the crop canopy.She referred to trials which took place in 2008 where an additional 60kg N/ha was applied in July for a crop that had already received 80kg N/ha. “There was no yield impact – the crop had already got its optimum canopy and no benefit of late N to supplement earlier applied N was seen,” she commented.Furthermore, Dr Sparkes said that even where fungicide use has an impact on canopy size and yield, applying more N alongside the fungicide (in July) could not be justified as it had no affect on yield.”This work is from only one year’s worth of data, but there is no evidence to suggest that crops which receive fungicides need more N,” she added.Continental comparisons
While UK growers are rightly praised for the continuing increase in average sugar beet yields in this country, there is the nagging question as to why some countries on the continent, such as France, produce average yields higher than in the UK.However, Dr Sparkes pointed out that mean daily temperatures are key for canopy development and when comparing sugar beet growing areas such as Lille, in France, with Norfolk, the average daily temperature was significantly higher in Lille giving crops there a significant advantage.”Because of warmer temperatures, canopies expand faster and reach peak canopy expansion earlier and so they can intercept a greater proportion of radiation.”She highlighted the example of Sweden, where yield rankings were lower than the UK because, although radiation ‘receipts’ are longer in summer due to the greater day length, the crops are sown later due to the cool climate and so canopy expansion is behind that of the UK.”Yield potential is largely determined by environmental conditions,” she pointed out.To conclude, Dr Sparkes said that a study of 27 sugar beet varieties in Recommended List trials over the past three years had showed that there was no evidence of a change in variety ranking as harvest is delayed through the lifting season. R&D
The impact of European regulation (having to produce more with less), new diseases and pathogen adaptation, and changes in the climate impacting upon crop growth and diseases, were just some of the challenges the UK sugar beet industry was facing for the future, said BBRO lead scientist, Dr Mark Stevens (left).He said it was key that all the tools and technologies available such as rhizomania resistant and BCN tolerant varieties, and neonicotinoids for aphid control were embraced to ensure future crops were delivered.He highlighted the example of stemphylium, a new disease to the UK which was found in Norfolk for the first time last summer. “It’s a concern and shows how pathogens can adapt, with spores potentially coming over the North Sea and impacting on the UK crop.”Standard fungicides that you are using to control the rusts and other common diseases in sugar beet are not suited to controlling stemphylium,” he warned, adding that widely used cereal fungicide active epoxiconazole has some activity, although more trials work was needed.Following an independent review of the BBRO’s crop protection research portfolio, Dr Stevens said that as many as 40 recommendations had been drawn up to ensure the organisation was focussed on tackling key areas for the future.
He highlighted a number of new projects, including research into the impact and control of the mangold fly, or leaf miner – normally successfully tackled with seed treatments. “We’ve seen greater activity in Norfolk, Suffolk, Lincolnshire and the Wash area, with mangold fly coming into the crop at a similar time to fungicide applications and then crops losing their canopies,” said Dr Stevens. “Seed treatments are doing a good job for the first 15 weeks or so, but after that the mangold fly is becoming a problem,” he added. Another new area of research will focus on the infection and re-infection by rusts and mildew, continued Dr Stevens, who said that there are populations of these diseases that need to be better understood. “A BBRO trial in Lincolnshire last year showed the clear benefit of disease protection in a fungicide-treated plot, but we were still finding small pustules of infection in the crop. We need to understand the diversity of populations of mildew and rusts and determine the source of infection of sugar beet crops,” he said.A third new area of research Dr Stevens highlighted was a project being undertaken by the University of Nottingham to better understand plant and beet cyst nematode interaction. He said that sophisticated scanning technology at the University would help to find out more about how sugar beet grows and how pests and pathogens affect rooting.This, he concluded, was vital considering that the latest BBRO survey showed that six per cent of sugar beet growing land in the UK was infested with BCN.
“The arable sector as a whole is facing a challenging future and sugar beet has a great track record exploiting tools and technology to promote yield. “New BBRO projects will support the drive for continued yield production and enhancement,” he concluded.New season optimism?
Also attending the event was SESVanderHave UK general manager Ian Munnery, who said that growers should look ahead to the new sugar beet growing season with optimism, despite longer-term concerns about the price they might be receiving for the crop in the future. “The campaign just coming to an end has produced some very good yields, as has been the case in the past few seasons, and if growers are seeing record yields on their farms then they aren’t doing much that is wrong,” he commented.”Our strategic objective is the same as it’s always been and we advise growers to push for yield. Plant at the earliest opportunity, preferably in the first week in March, stick with what you know in terms of crop management and inputs and lift later where possible.”Mr Munnery said that growers should ensure they are pragmatic in their approach to growing the crop at 24/t by maximising yield and minimising risk,” he added.”It’s been a bit doom and gloom in recent months but, in reality, if you look at other sectors like potatoes or oilseed rape for example, where prices have struggled, sugar beet growers have benefitted from a relatively secure market in Europe.”UK growers have far less to worry about than continental growers in terms of pests and diseases, and with the markets usually cyclical, sugar beet is likely to get back to better prices in the long term.”