Plant breeder RAGT Seeds unveiled a new winter wheat variety with Barley Yellow Dwarf Virus (BYDV) resistance, the result of a two-decade development programme, at a seed trade meeting held near Cambridge earlier this week. In another first, the company intends to market the variety through a grower royalty system as used with some of its oilseed rape varieties.

RGT Wolverine is a high-yielding nabim Group 4 feed wheat which will complete NL2 trials this year. It will then be under consideration for AHDB’s Recommended Lists for 2020 that are published in December. The variety may also suit some northern Europe markets.

The breeding breakthrough comes from the introduction of the Bdv2 gene from a wild goat grass, Tinopyrum intermedium, first identified by the Australian state research body CSIRO. Work on this trait had started in Cambridge at PBIC, when the breeding operation was still owned by Unilever, before its subsequent sale to Monsanto and then RAGT Semences in 2004.

RAGT geneticist John Batson says the company has introgressed the Bdv2 gene into the 7DL chromosome of wheat to convey resistance to a broad spectrum of BYDV viruses. He is confident that its long availability in Australia means the resistance is unlikely to break down quickly.

European cereals breeding manager Dr Richard Summers described the Wolverine gestation process as a marathon, not a sprint. While the Bdv2 gene had been available for some time, the difficulty was introducing it into the company’s elite wheat breeding material to produce a variety that was both BYDV resistant and had a commercially attractive yield potential. This has been achieved by drawing on material from across RAGT’s pan-European plant breeding resources.

The company has proven that the variety works, and works in the UK, added Dr Ruth Bryant. She outlined trials in three key arable regions of the England, where early sown wheat plots were infected with high levels of aphids containing BYDV. The trials showed a good level of BYDV resistance, although not complete. The incomplete resistance is in fact a strength – it means there is less pressure for pathogen to evolve resistance mechanisms.

Independent agronomist Keith Norman observed that around 40% of the UK wheat crop is vulnerable to BYDV in the absence of neonicotinoid insecticides. He cited AHDB figures showing that the disease can cause up to 60% yield loss – if left untreated, up to 82% of the UK wheat crop could be at risk – a potential loss of some £136m worth of crop.

The loss of neonics will only increase the selection pressure on the remaining pyrethroid chemistry, Mr Norman argued. In addition, policy moves such as the post-Brexit ELM scheme, and increasing maize growing for AD biogas systems lead to higher aphid vector numbers.

RAGT Seeds managing director Simon Howell says the variety will be sold at a slightly lower base cost but will be subject to a self-declared grower royalty payment collected through the Breeders Intellectual Property Office (BIPO). The company started using this grower risk reducing scheme for three of its oilseed rape varieties in spring this year. Mr Howell is confident that BIPO will be able to cope with the additional cereal volume – the system has recently been upgraded , with a move to online grower declarations to make it more user-friendly.

RGT Wolverine will be priced (seed and royalty combined) to reflect the average £31.50/ha cost saving from not having to treat crops with insecticide to control the aphid vectors of BYDV. There will also be workload savings and environmental benefits from reducing insecticide usage through the genetic resistance.

RAGT will have some 3,500 tonnes of Wolverine seed available for autumn 2020 winter wheat plantings. There are new BYDV resistant varieties in its breeding pipeline.

More information from RAGT cereals and oilseed product manager Tom Dummett on tdummett@ragt.fr or tel: 01799 533703.