Early applications of foliar nutrition could be key to helping this year’s sugar beet crops establish after the effects of the difficult winter.
That is the message from Procam agronomist Ian Jackson who says slumped soils caused by heavy rainfall have caused havoc for creating good seedbeds, with poorer seedbeds, in turn, potentially delaying sugar beet emergence.
And even though emergency authorisation for neonicotinoid seed treatment use on sugar beet seed has been granted this season, early foliar nutrition could still be an important agronomic tool to help crops grow past their most vulnerable 12-leaf stage for aphid-borne virus transmission, he adds.
“It’s important that sugar beet achieves full ground cover as quickly as possible,” explains Mr Jackson, “not least to allow it to intercept maximum sunlight. But in many ways, sugar beet starts with a problem – in that it is drilled into cooler soils, which are unable to supply sufficient nutrients in its seedling stage.
“Even after an autumn maintenance application of phosphate (P) and potash (K), spring applications of these macronutrients are still required to counter the soil’s inability to supply adequate levels. However, soil-applied P can become locked onto the soil before it has achieved its goals, and K needs to be applied ahead of drilling to avoid seedling scorch, but the compaction from an extra set of wheelings can cause up to a 30% reduction in yield.”
In response, to give sugar beet crops an early boost, Mr Jackson suggests applying a multi-nutrient foliar treatment with the first two herbicide sprays, such as Pro+ NutriBio. This provides a balanced range of macro and micronutrients complimented with brown seaweed extract, he says, before switching to a polymer urea treatment, Pro+ N-Viron PCA, plus boron with the third herbicide spray, to supply a sustained release of nitrogen (N) to help expand the leaves across the rows.
“In farm observations, this approach has significantly increased the speed of ground cover over the last three years,” says Mr Jackson. “Last year, treated crops grew through the early 30 degree heat which stopped most crops in their tracks for three weeks. Other crops give very good responses to foliar urea polymers, but sugar beet seems to be in a different league.
“Indeed, two growers used no solid N for a second year as they were impressed with how Pro+ N-Viron had performed previously when N was uneconomical to purchase. These crops also performed slightly better than most crops in their areas with a much reduced cost and prospects of carbon reduction income in future.
“Including boron at this stage is a very pertinent consideration this season after the wet winter because it’s very leachable. Boron is needed during rapid cell division and deficiencies result in heart rot in sugar beet, something which is critical to avoid.”
Ian Jackson, ProCam
Where aphicides are being applied to target virus transmission, Mr Jackson says these must be applied according to when aphid thresholds have been reached.
To maximise spray coverage, water volumes should be kept up and angled nozzles used, he notes. “Good spray coverage is needed on each leaf in order to get the best protection, and consider taking the opportunity to also apply manganese.
“Sugar beet is very sensitive to manganese deficiency. It’s a nutrient heavily involved in photosynthesis, so deficiency is a real issue in a crop that’s harvesting light to produce sugar.”
