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The Cream of the Crop

The Cream of the Crop

Genetic improvement of vegetable crops

The Warwick Crop Centre provides global seed companies with research on the genetic diversity of vegetable crops. Our research has enabled the identification and development of vital resistance genes to combat viruses that significantly impact on crop production, and the livelihoods that rely upon them, worldwide. Professor John Walsh’s research on turnip mosaic virus (TuMV) identified recessive genes that have been introduced into breeding lines to provide resistant plant varieties that are due to be released in the next 1-2 years. Resistance has also been identified to turnip yellows virus (TuYV; which results in losses of between £67 - £180 million each year in UK). Working with global companies such as Syngenta and Limagrain, Professor Walsh’s research has changed their understanding of the severity of the virus, informed their breeding programmes and raised their customers’ awareness of the way viruses impact on crop production.

The challenge

Turnip mosaic virus and turnip yellows virus significantly impact field vegetable crops worldwide, affecting crop weight yields by up to 64% and reduce yields of oilseed rape by up to 30%, detrimentally affecting supply and impacting on livelihoods.


Our approach

Funded by a BBSRC Crop Science Initiative grant, and facilitated by a BBSRC CASE studentship with Syngenta, Professor Walsh mapped and identified the gene involved in broad-spectrum resistance to TuMV. His research identified that the resistance gene was recessive and original, enabling the resistance mechanism to be patented. Identification of the gene facilitated the development of markers that have facilitated the rapid identification of plants carrying the resistance gene. This enabled swift introduction of the resistance gene into commercial breeding lines.

Professor Walsh subsequently investigated the transmission and control of TuYV, revealing its prevalence in oilseed rape and vegetable brassica crops. He has identified and mapped a number of new sources of resistance to TuYV in oilseed rape and vegetable brassicas.

Our impact

Syngenta purchased the TuMV resistance patent rights in 2012 and has since introgressed the gene into several parental breeding lines. Professor Walsh’s development of the gene marker accelerated their international resistance breeding programme by a substantial 5 years, producing significant financial savings. As of 2021, Syngenta has a number of Chinese cabbage varieties that display the resistance, which are anticipated to allow for better penetration of the European and Chinese markets.

Professor Walsh has also worked closely with Limagrain, Tozer Seeds, Sakata, Rijk Zwaan and Enza Zaden, Elsoms, Hazera and Corteva on turnip yellows virus. TuYV affects oilseed rape with yield reductions of up to 30%, resulting in losses of up to £180 million in the UK, and greater losses in mainland Europe. It also significantly reduces the yield of vegetable brassicas. His research demonstrated almost 100% incidence of the virus in some crops, enhancing Limagrain’s understanding of the severity of the virus, informing their breeding programmes and raising their customers’ awareness.

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