An unseasonably early harvest and record-breaking temperatures have increased the risk of yield loss from barley yellow dwarf virus (BYDV). BYDV can cause yield losses of 30-40 percent in warm autumns and with the ban on neonicotinoids researchers have been trialling new ways to control the disease.

Orion Future Technology conducted a trial with NIAB, to investigate the effect of a range of treatments to protect winter cereals against BYDV. Trials using a silicon biostimulant foliar spray either with a pyrethroid or as a standalone alternative have shown encouraging results. NIAB agronomist, Dr Syed Shah explains,

“We applied three sprays on KWS Extase winter wheat that emerged September 19^th, 2021, on a high-risk site in south Devon. One of the most successful treatments was a combination of Sirius, a silicon biostimulant mixed with a well-established pyrethroid product. However, for those looking to protect both crop and beneficials, the results from the silicon only treatment were very encouraging. More small plots and on-farm trials will be conducted to validate the results.”

Combining the biostimulant with the pyrethroid saw a yield increase of 17.2%, over the untreated area. Using Sirius alone improved yield over the untreated by 5.5%, compared to a 9.7% yield increase achieved with a pyrethroid.

Each application was made 170 day degrees (DD) from emergence, with applications on October 13^th, October 21^st, and November 9^th. The trial found the use of Sirius helped to strengthen the plant’s natural defences against biting pests such as aphids. It strengthened cell walls and increased cuticle thickness, which reduced aphid feeding. This also reduced the risk of virus transmission.

James Kennedy, Managing Director, Orion FT explains:

“Silicon must be in a plant available form and that is where Sirius has a unique advantage. Orion’s iNHiB™Technology makes silicon plant available in a monosilisilic acid form. It is very compatible and can be added to a tank with other products or used as a standalone alternative.”

Drilling later has been used as a means of minimising risk, but with such an early harvest caused by the dry summer, many growers have drilled earlier than has been possible in previous years. Warm autumn conditions across the UK are allowing aphid populations to increase rapidly. The first nine months of 2022 have broken the record to become the warmest on record, according to the Met Office, and September was 0.5°C higher than the long-term average for the month, with an average temperature of 13.4°C.

“Responding to these changes in climate is essential to stabilise yields. In a warm autumn it is advised to protect crops early and having a new biostimulant as an alternative or addition to a pyrethroid will be welcomed by growers should autumn temperatures continue in this way,” concludes Mr Kennedy.