Safeguarding, evaluating and valorizing fruit tree genetic resources in Belgium: Insights from nearly half a century of unsprayed orchard management

Summary

In response to the rapid genetic erosion threatening Belgium’s fruit tree cultivar heritage, the Walloon AgriculturalResearch Centre (CRA-W, Gembloux, Belgium) initiated nationwide prospection campaigns in 1975 with support fromcitizens. These campaigns aimed to collect and conserve the country’s highly diverse fruit tree genetic resources (FTGR),including historically significant amateur-bred and landrace cultivars, for future breeding efforts.Since then, the CRA-W has maintained a diverse collection – primarily apples (1,629 accessions) and pears (1,198 accessions),but also cherries (355 accessions), plums (236 accessions), grapes (98 accessions), and peaches (29 accessions) – in ex situunsprayed repository and experimental evaluation orchards.This approach makes it possible to assess these cultivars for multiple traits related to their tolerance and adaptability tobiotic and abiotic stresses. This long-term evaluation method enables the identification of numerous quantitative traits andtheir impact on robustness and stress tolerance. Moreover, CRA-W has actively sought ways to promote the sustainable useof FTGR through partnerships with public institutions, private stakeholders and citizens. One key initiative was the gradualestablishment of a nursery network governed by a participatory fruit tree quality charter, coupled with a traceability systemfor high-quality propagation material.This initiative led to the release of 33 well-performing heritage cultivars, notable for their sufficient robustness and diseasetolerance, for use in both amateur and professional orchards. A decade later, a dedicated apple pre-breeding and breedingprogramme was launched to harness the extensive FTGR collection as a source of quantitative disease tolerance, robustnessand quality traits.