Cherry genetic resources in Europe investigated and safeguarded
Late in spring and in mid-summer, sweet cherries can easily be found in the market. Consumers really enjoy such a bright, sweet and juicy fruit, and it can easily seem as if there is an endless variety to choose from. On closer inspection, however, most of the cherries in the market derive from only a few dozen varieties. Consumers would probably be surprised to learn that a few thousand sweet cherry varieties exist in the world, and that this diversity is crucial to breeders to create new cultivars that will adapt and keep productive in the future, under more difficult climatic scenarios.
The diversity of traditional varieties should be protected on farms, with incentives to do so, but it is genebanks and, more generally, dedicated field collections that play a key role in preserving this heritage of genetic resources. Today, the greatest conservation efforts for cherry are in countries from Europe to West Asia, where this crop is native. In Europe, a large diversity of landraces is preserved in tree field collections, where the morphological and genetic richness can be properly described and made accessible for research and breeding purposes. Many of these collections participate in an EU network – the European Cooperative Programme for Plant Genetic Resources (ECPGR), that since 1980 has put all its efforts and resources into coordinating the conservation and use of plant genetic resources.
Cherry experts get together
In 2016, experts on cherry genetic resources from ten EU institutes and members of the ECPGR Prunus Working Group collaborated in the EU.CHERRY project, aimed at documenting and communicating the richness of cherry diversity in Europe. EU.CHERRY partners also joined forces with other cherry experts participating in a COST Action on Cherry. Together, they identified 324 valuable varieties in their collections, mostly cherry landraces original to their own countries, under the management and control of their government and in the public domain, endowed with interesting agronomical traits for breeding or cultivation.
Leaf samples from these cherry varieties from 23 countries were sent to East Malling Research (EMR - UK) for common genetic analysis with SSR markers. The genetic analysis allowed the identification of 192 unique allelic profiles, but also discovered that 132 were just duplicates ‘hidden’ under different varietal names, some of which were truly unexpected!
New accessions for a European Collection (AEGIS)
Another priority goal of the EU.CHERRY project was to include sweet cherry accessions in the decentralised European Collection, established under the AEGIS (European Integrated Genebank System) vision. Within this system, countries guarantee long-term conservation on behalf of the European region and make genetic resources of all crops available to anyone , based on the terms and conditions of the FAO International Treaty on Plant Genetic Resources for Food and Agriculture.
As 114 out of the 192 genetically unique varieties are maintained at EU.CHERRY partners’ collections, and were accurately described with passport (name, origin, date of acquisition, etc.) and with morphological or agronomic data during the EU.CHERRY project, they are immediately good candidates to compose the European cherry Collection. Their passport data have been compared with existing entries in the European Search Catalogue for Plant Genetic Resources (EURISCO) and partners have been encouraged to take due action to add the missing ones to the catalogue, which is a necessary step to make them officially visible to the general public, before they can be included in the European Collection.
Cherries are just one of the important species of interest to GenRes Bridge in its efforts to ensure the long-term conservation and sustainable use of genetic resources in Europe. The documentation catalogue EURISCO, the AEGIS European Collection of plant genetic resources and the European Evaluation Network, which together help to conserve cherry diversity and make it available, are some of the key elements for in situ conservation. The GenRes Bridge project will aim to reinforce them and integrate them into an overall European genetic resources strategy.
Acknowledgement: We would like to thank the public library 'A.Saffi' in Forli, Italy for the image of table 45 from the set of 27 manuscripts of 'Plantarum Collectio' by Cesare Majoli which the library conserves.
