Complementary strategies for ex situ conservation of coffee (Coffea arabica L.) genetic resources. A case study in CATIE, Costa Rica
It is now well recognized that an appropriate conservation strategy for a particular plant genepool requires a holistic approach, combining in a complementary manner the different ex situ and in situ conservation techniques available. Selection of the appropriate methods should be based on a range of criteria, including the biological nature of the species in question and the practicality and feasibility of the particular method chosen, as well as the cost-effectiveness and security afforded by its application. Considerations of complementarity with respect to the efficiency and cost-effectiveness of the various conservation methods chosen are also important. Complementarity is a flexible concept, which evolves with the availability of techniques aiming at conserving, propagating and characterizing the genetic resources in question. Research on the development of complementary conservation strategies gained momentum at the beginning of the 1990s, and is coordinated by Bioversity International (Bioversity). This research area is of particular relevance for species with seeds displaying non-orthodox storage behaviour, whose traditional ex situ storage method is the field genebank. In some ways, this method offers a satisfactory approach to conservation. The genetic resources under conservation can be readily accessed and observed, thus permitting detailed evaluation. However, there are certain drawbacks that limit its efficiency and threaten its security. The genetic resources are exposed to pests, diseases and other natural hazards, such as drought, weather damage, human error and vandalism. Field genebanks are costly to maintain and, as a consequence, are prone to economic decisions that may limit the level of replication of accessions, the quality of maintenance, and even their very survival in times of economic stringency. Even under the best circumstances, field genebanks require considerable inputs in the form of land, labour, management and materials, and, in addition, their capacity to ensure the maintenance of much diversity is limited. For many years, non-orthodox seed research has been recognized by Bioversity as an area of critical importance for the conservation of plant genetic resources, and numerous projects on this topic have been or are being implemented in collaboration with research institutions and genebanks worldwide. Many of these projects have focused on the development of cryopreservation, i.e. the storage of biological material at ultra-low temperature, usually that of liquid nitrogen (-196°C), as cryopreservation is the only method currently available to ensure the safe and cost-effective conservation of germplasm of non-orthodox-seed species. Recognizing the tremendous potential interest of the results achieved at IRD with cryopreservation of coffee seeds, Bioversity decided to support a research programme aiming at transferring and testing on a large scale in a genebank located in a developing country the freezing protocol developed in France. This was performed in 1998–2000 in the framework of two successive projects with IRD and CATIE, Costa Rica. CATIE was an ideal partner as it fulfilled the set of criteria required for participation in such a project. Indeed, CATIE holds one of the largest field collections of coffee worldwide, mainly of Coffea arabica. CATIE's fully equipped biotechnology laboratory includes all the facilities required for cryopreservation and molecular biology research, as well as highly skilled scientific and technical staff. Moreover, Bioversity and CATIE have a long and successful collaboration history in various areas, including cryopreservation of tropical plant germplasm. At the time of the initiation of this programme, IRD staff were also working in CATIE on a collaborative research project on the characterization and rationalization of the CATIE coffee germplasm collection using molecular tools. We were thus in an ideal situation to study how new technologies (molecular biology and cryopreservation) could be efficiently employed to complement more classical ones to characterize and rationalize an ex situ germplasm collection, and to improve its conservation status.
To our knowledge, the work described in this publication represents the first example of the application of these techniques in a genebank located in a developing country, in the framework of the development of an ex situ complementary conservation strategy for C. arabica, i.e. a crop of commercial importance at the global level. We hope that this publication will help in stimulating research on complementary conservation strategies for other problem crops, as well as on the biotechnological tools required to implement them.
Author: Engelmann, F.; Dulloo, M.E.; Astorga, C., Dussert, S.; Anthony, F. (eds.)
Pages: 61 p.
Publication Year: 2007
Publication Format: B5