Treating potato and sugar beet crops now with nitrogen fixing bacteria biofertilisers could ensure plants have essential nutrients available during key growth stages if dry weather compromises uptake of artificial fertiliser.

Syngenta Technical Manager, Andy Cunningham, advocates an early season Vixeran application locks the nitrogen fixing capability into the plant and the soil biosphere through the growing season.

Trials have shown that the optimum timing for application in potatoes is around the onset of tuber initiation, and for sugar beet at the four to eight true leaf stage (BBCH 14-18), he advises.

“The target is to have sufficient leaf area for uptake into the crop, but also where spray can reach the soil and colonise the root zone with the nitrogen fixing bacteria, which will convert atmospheric N into available nutrient for the plant.

“That’s essential when the crops are going through rapid vegetative growth and setting the all-important yield potential for root development,” says Andy.

With some areas of the country receiving just 5 to 10% of average rainfall during March and the first three weeks of April, particularly in the primary root crop areas of eastern England, the nutrient availability of applied artificial fertiliser would have been seriously limited.

“Soil temperatures in most areas are now optimal for Vixeran biofertiliser activity, which quickly starts to generate readily available N to match crop growth, even in dry conditions,” he adds.

Early nitrogen has been identified as especially important for the formation of a strong green leaf canopy in sugar beet. Results of recent trials in Holland have shown a single Vixeran application at the five to eight leaf stage in sugar beet, before the crop covered the ground, delivered a 4 t/ha yield increase and 0.7% improvement in sugar content over a standard140kg N/ha fertiliser input. The trial also demonstrated that Vixeran could more than compensate with yield and sugar content when the artificial N was reduced by 40kg/ha.     

The specific endophytic bacteria strain of Azotobacter salinestris in Vixeran has been selected to work effectively in typical weather conditions in the UK and northern Europe, as well as improving resilience against periods of climatic extremes.

For ease of application, Andy reports Vixeran is tank-mix compatible with blight fungicides including Revus and Evagio Forte in potatoes, as well as Priori Gold/Angle disease control in sugar beet. It can also be applied at the same timing with Quantis biostimulant, to manage temperature stress in both root crops. 

For further information on Vixeran, please visit: https://www.syngenta.co.uk/biologicals/vixeran