Noted for their colour and scent, roses are one of the most important ornamental flowering plants grown worldwide, with a yearly estimated production of 18 billion cut stems and up to 80 million potted roses.
In spite of the plant’s popularity and industry importance, rose viruses have not been studied in detail in the UK since the 1980s. But, recent advances in scientific techniques, such as high-throughput DNA sequencing, provide new opportunities to improve our understanding of the viruses. By working with the RHS and industry partners to understand the trade, the work will help to future proof against new and emerging threats such as Rose rosette virus.
Rose rosette virus causes reddening on newly emerging shoots, excessive thorn production, abnormalities and eventually plant death. Not yet present in the UK, Rose rosette virus is considered one of the plant’s greatest risks and responsible for the destruction of entire collections in the USA and Canada. Recently reported in India, the virus is spread by a four-legged microscopic mite transported on plants, insects, wind or contaminated clothing.
The research is being delivered through the RHS and IAFRI, a joint venture between Newcastle University and Fera Science Limited and with the support of David Austin Roses. PhD researcher, Ines Vazquez Iglesias, will analyse hundreds of samples from RHS collections, gardens and nurseries across the UK at Fera’s Sand Hutton research facility with the findings published in 2019.
Common problems afflicting UK garden roses include:
- Mottled leaves and weakened plants caused by rose viruses such as Strawberry latent ringspot virus and Arabis mosaic virus
- Fungal problems on the leaves including rose blackspot, powdery mildew and rose rust, causing disfigured growth and lack of vigour
- Root problems caused by Phytophthora root rot and honey fungus, leading to plant die-back and eventual plant death
Gerard Clover, Head of Plant Health at the RHS, said: “Roses are favoured by gardeners for their wide range of colours and scented blooms with their versatility making them a stalwart of gardens across the country. With new pest and disease threats waiting in the wings it’s important we apply the latest tools and techniques to protect gardens and support the UK’s horticultural industry.”
Nicola Spence, Defra Chief Plant Health Officer, said: “We want to be the first generation to leave the environment in a better state than we found it and protecting our plants, such as roses, from pests and diseases is a key part of that ambition.
“Rose rosette virus is not present in the UK and we are continuously working to ensure that foreign threats are kept away. However, we also need to better understand the threat they pose and this research by Newcastle University will provide essential intelligence on how to tackle these emerging pests and diseases.
“Once again, I urge everyone to source their plants from reputable nurseries and to remain vigilant for threats by practising good biosecurity.”
Ines Vazquez Iglesias, PHD researcher, said: “This year an RHS bursary provided an opportunity to see first-hand the devastation that rose rosette virus has had in the US. What was once a blooming garden of roses had been reduced to hundreds of dead or dying plants. My research is intended to educate industry and gardeners as to the risk posed to the rose by new and emerging viruses and protect the UK’s gardens for the future.”
For more information:
Royal Horticultural Society