Trials completed by Orion Future Technology on UK grape vines have shown that using silicon as a foliar spray can help to combat excessive accumulation of copper, which can affect the sensory qualities of wine. The trials found that by applying a silicon-based bio-stimulant, the plant’s natural defences against mildew infection and aphid feeding damage were strengthened.
Technical specialist at Orion FT, Kate Williams, said: “Our trials showed an increase in silicon uptake of 30% following the application of Fossil, a silicon bio-stimulant, as a foliar spray. The product also helped the vines to take in significantly more zinc and iron, both essential for the formation of sugars. Optimising nutrient levels is a key property of bio-stimulant products,”
Higher levels of copper can cause a reduction in the levels of beneficial bacteria and fungi in the rhizosphere. By reducing the reliance on this and filling the gap with a silicon bio-stimulant, improvements can be seen in soil health as well as naturally strengthening the plant. Excess copper in grape juices can have a negative effect on the thiols of some wines, adversely affecting the aroma. A silicon bio-stimulant can be mixed with a fungicide to offset this.
Ms Williams continued: “We are not advocating that growers stop using fungicides. However, our trials show that by including a silicon bio-stimulant as part of an IPM approach, vines will carry less copper and more micronutrients, which will improve plant health, yield and also improve the aromatics of the wine.
“Our findings provide evidence for the potential of at least partially replacing conventional fungicides. By protecting soil and biodiversity it also has the potential to make viticulture more sustainable. Silicon applications are a relatively low-cost option, can be added to a tank with other products, and have the added advantage of complying with the principles of the Sustainable Use Regulations.”
