Maximising leaf cover and maintaining it throughout the season is one of the most important measures growers can take to influence yield and protect sugar beet crops, according to Steve Wilcockson, sugar beet expert at Newcastle University.
Full and healthy leaf cover improved competition against weeds and protected roots from frost damage as well as intercepting more light, which increased yield, he said during judging for the second round of the Farmers Weekly and British Sugar Beet the Best competition.
In the second of three rounds in the competition, growers had to protect their virtual crops from a number of pests, weeds and diseases to keep yield potential as high as possible.
Plant population was key to getting a full canopy and growers should be aiming for 90,000 plants/ha, said Dr Wilcockson. “With this number of plants you should hit the jackpot in terms of root yield, sugar concentration and minimum alpha-amino N content.”
Any lower than this and some parts of fields would not achieve the optimum canopy cover and yield. Leaf cover of 100% would also give the highest leaf area for light interception and competition against weeds, he added.
Seed rates required to achieve this population could vary significantly between farms and individual fields, said Mark Stevens, head of crop protection for Broom’s Barn. “You need to know your conditions and rate of establishment to get to this population.”
Achieving a 90,000 plants/ha population would also produce optimum-sized beet to prevent excessive soil tares associated with smaller roots at higher populations, said Dr Wilcockson.
British Sugar’s Paul Bee said: “Plant population is one of the key messages we are trying to get across, so it’s great so many growers are getting it right.”
To prevent bolting, growers who are planning to drill in March should choose varieties carefully. Field choice was another important consideration as soil temperatures could drop by different amounts, according to soil type, location or topography.
Spotting pests and disease early and removing weeds such as volunteer potatoes or oilseed rape would also help reduce yield-robbing effects, the panel said.
Clopyralid was the chemical of choice for volunteer potato control and oilseed rape volunteers should be treated with a herbicide at the first opportunity.
If crops were showing signs of speckled yellows in late May, growers should spray with a manganese sulphate fertiliser, they said.
The most effective insects for controlling aphids were ladybirds and parasitic wasps.
Some advisers who entered the competition suggested growers should decide irrigation policy according to contract fulfilment potential. The panel said soil moisture deficit should be the fist consideration followed by the potential financial return from the crop.
Consider harvest strategy carefully
Round three is now open and growers are tackling harvest and delivery decisions including protecting beet from freezing conditions.
Minimising the quantity of beet being stored in clamps was a key consideration as roots would be better protected from freezing temperatures when left in the ground, said Mr Bee.
Growers needed to prioritise crops for harvest according to condition, protect clamps where beet needed to be stored and think carefully about their lifting strategy, he said.
Harvester set-up was an important consideration, particularly where crowns had been frozen, and correct crop handling would prevent root damage prior to delivery.
More than 200 entrants were battling it out in the Beet the Best competition this year and the level of knowledge among entrants was impressive, said British Sugar’s Paul Bee.
“Growers, advisers and students have shown a great understanding of the key technical elements required to grow a 100t/ha sugar beet crop.”
It was also reassuring that technical messages from researchers and industry experts were filtering down the system and being used practically on-farm.
The third and final round will close at the end of December and winners will be announced in January. Successful entrants from each category will be taken on a study tour looking at beet growing and sugar production in Spain.