United Kingdom - RAGT’s BYDV-resistant wheat

Date:03-02-2023

RAGT’s breakthrough Genserus (genetic security against virus) varieties that are resistant to the potentially highly damaging barley yellow dwarf virus could help growers qualify for a £45/ha payment for not using insecticides under the Environmental Land Management (ELMS) scheme.

The latest ELMS update includes several new Sustainable Farming Incentive standards, including one that covers Integrated Pest Management. Within this is an action that rewards growers who abstain from using plant protection products containing insecticides on a designated area of land for the duration of the three-year agreement.

This can be done on a single area of land, or the area can be moved each year. Defra says the initiative will help to support an IPM approach by managing crop pests in a more sustainable way that limits the impact of insecticides, while improving water and air quality and increasing biodiversity.

Tom Dummett, RAGT Seeds’ cereal and OSR product manager, says the Genserus pipeline includes high-performance varieties that are resistant to both aphid-borne BYDV and orange wheat blossom midge, offering the very real prospect of insecticide-free wheat that would qualify for the £45/ha payment.

″Growers who want take advantage of this payment can de-risk themselves by growing a Genserus variety,″ says Tom.

″The resistance trait offers protection against BYDV from the day the wheat is planted to the day it is harvested, for less than the cost of a single pyrethroid spray which may only control the aphid vectors for a few days.

″Very often two or three sprays may be needed or, as was the case in many areas last autumn, even four sprays.

″Genserus varieties greatly simplify crop management, removing the need to monitor and control aphid populations with foliar-applied insecticide sprays while benefiting the environment.″

The first winter wheat variety with this double resistance, a Group 4 hard type, will be launched commercially this coming autumn.

″Insecticide-free wheat has obvious attractions within all markets,″ says Tom. ″We also have some very promising milling wheats resistant to both pests that are excelling in screening trials. They have been extensively tested by end users and all are labelled as high-quality bread wheats. They will be ready for launch in 2025.

″In addition, we have a very large pipeline of other varieties mostly with virus resistance and midge resistance, all from different backgrounds and different quality classes.″

Robust resistance

The resistance gene in current Genserus varieties, Bdv2, was introduced from a wild goat grass and has been used commercially in Australia for two decades and has proved robust, with no signs of breaking down.

RAGT has also been testing the concept in the UK under extreme pressure for the past three seasons, comparing several of the company’s high-performance BYDV-resistant varieties against some widely grown Recommended List wheats.

The BYDV-resistant wheats plots showed no symptoms obviously associated with the disease, but conventional varieties were all affected, some severely.

All wheats containing the Bdv2 gene are sold under RAGT’s new Genserus brand (genetic security virus). A new logo appears on all branding, and each variety will begin with the letter G, ensuring the resistance technology stands out from the pack.

Assessing companion crop prospects in cereals

The new IPM standard also includes a £55/ha payment for establishing a companion crop that will grow with an arable or horticultural crop on land entered into this action each year over the three-year agreement. This can be on a single area of land or the area can be moved each year.

Although details remain sketchy, RAGT trials investigating the use of companion crops on winter wheat and spring barley is very much in line with government thinking, says Tom.

The winter wheat trial is examining the effect of five different companion crops on the performance of a range of RAGT winter wheat varieties.

″The ultimate aim is to enable growers to match their RAGT wheat varieties to cover crops,″ says Tom. ″There are some very complex mixtures out there that contain multiple species, but what does each constituent do? We aim to find out what works and what doesn’t, and how our varieties respond.″

The cover crops were sown on 22 August, followed by 14 RAGT wheat varieties on 14 November. These were direct drilled across the different covers and one fallow plot, as first and second wheats.

″We expect the wheat to grow away from the catch crops, which will have had plenty of time to condition soils and capture nitrogen,″ says Tom.

″Last year we saw some significant differences in green area index between varieties drilled into fallow and others drilled into catch crops, although it is too early to draw any conclusions,

″But Phacelia did stand out – the following wheat had double the GAI of compared with wheat after fallow and gave a significant increase in GAI compared with other cover crop species.

″Phacelia does have a very fibrous root, so it might have enabled the crop to put down roots more quickly, providing better access to nutrients.

″It will be fascinating to piece all the results together at the end of the season, including yield and quality data, to see if we get a similar result again.″

Companion crops used:

• Phacelia

• Phacelia, radish, linseed, crimson clover

• General purpose soil improver containing legumes, forbs and brassicas

• As above + vetch and crimson clover

• Biofum Autumn plus (mustard mix to combat take-all)

In the spring barley trial, RGT Planet spring barley is being grown alongside a range of clover species and after a range of overwintered catch crops to assess whether nitrogen applications can be manipulated and reduced without affecting yield or quality.

A range of different clovers were drilled into the spring barley seedbed in the early spring following overwinter fallow or one of four catch crops that had been sprayed off in early January. These were vetch, Phacelia plus vetch, phacelia and Fix N Blend, providing a nitrogen source, a nitrogen sink and both source and sink.

″We’re looking to see whether the companions retain more soil N or create more and see which will work best in combination with the clover companion crop,″ says Tom.

″This should help us produce guidelines to help growers reduce inorganic N use in the barley while still hitting yield targets and contract specification.″