The plants, tested positive for the Cucumber Mosaic Virus and an unnamed potyvirus in 2011, threatened the survival of the Collection, so a pilot project was set up to find out whether apical meristem micro-propagation of plants from the collection would produce virus-free material.
A cash bursary from Brother UK in 2012 meant that Collection holders, David and Penny Ros were able to send a number of cultivars for micro-propagation. To date this has proved successful in 11 of the first 12 cultivars, and sufficient material has been obtained to permit viral testing in three cultivars. All three tested negative for the viruses, which means that the micro-propagation has successfully removed them.
David and Penny are now confident that with good 'housekeeping' it should be possible to protect new plugs from re-infection and provided the plants appear healthy they should be able to make material available to others when requested.
Speaking on the project Penny said; “The project has undoubtedly been costly, but having spent so much time and effort building up our collection, and learning about plant genetics, we were keen to keep it intact. A number of excellent cultivars, which are not commonly available, have been identified and it is hoped that sales of these plants will help offset some of the costs that have been incurred.”
Plant Heritage Plant Conservation Officer Mercy Morris said: “It is a long-term and costly undertaking to clean up a collection in such a situation and it is testament to the dedication of the Collection Holders that they have done this. It will be interesting to see whether virus infection has formed a part of the characteristics of the plants we know in commerce.”
Plant Heritage is the registered charity formerly known as the National Council for the Conservation of Plants and Gardens. As the world's leading cultivated plant conservation charity, Plant Heritage's flagship is the National Plant Collection® scheme.
There are more than 620 National Plant Collections in Britain. Each collection is a 'living plant library' dedicated to a specific genus, from Abelia to Zingiber. It may contain thousands of different cultivars, such as Dahlias, or just a handful – Lily of the Valley, for example – representing an extraordinary legacy of genetic diversity. By seeking out these plants, many no longer commercially available, propagating them, researching their history and properties and making this knowledge publicly available, Collection Holder are custodians of biodiversity. For medial researchers, historians, ornamental plant developers, amateur gardeners and conservation professionals tasked with reintroducing threatened species to the wild, Plant Heritage's collections are an essential and internationally significant resource.
Almost half of the collections are in private ownership and include allotments, back gardens and large estates. Collections are also maintained by local authorities, universities, agricultural colleges, schools, arboreta, botanic gardens and nurseries and there are also a number of collections on properties belonging to English Heritage, The National Trust and The National Trust for Scotland.