The objective of this project is to upgrade the quality of European hardwoods by vegetative propagation of elite specimens which have a proven superiority in growth and quality. The extensive variation within existing wild populations and in provenance and progeny trials already established for over 40 years in partners states will be exploited and captured. The method is to select and propagate superior genotypes of Quercus (Oak), Castanea (Chestnut), Prunus (Cherry), Ulmus (Elm), Acer (Sycamore), Fraxinus (Ash), Fagus (Beech), Juglans (Walnut), Camellia, Tilia (Lime) and Betula (Birch). Efficient utilization of these important genetic resources requires the development of efficient methods for large scale propagation, dissemination, and conservation. This can be best achieved by applying advanced biotechnological methods of propagation in conjunction with utilization of seed orchards and conventional procedures.
Elite plants of each species (many clones) have been identified and mapped in several countries. They have been propagated (grafting, cuttings) and used to establish clone banks and initiate sterile cultures in vitro. Initiation and establishment in vitro of viable shoot cultures from elite/adult trees is a difficult step but it has been achieved for most of the species listed. The efficiency of establishing cultures from juvenile plants was higher than for adult trees but useful information was obtained on sterilization, culture media and the selection of the most responsive buds on adult trees. Analytical procedures were modified for measuring endogenous hormones and key enzymes in tree cultures. Such analyses have given key information on the physiological responses of tissues during culture establishment and root initiation. Proliferating shoot clusters were obtained for most species (Alnus and Acer excepted) and the propagation rate varied among species and clones. Procedures were developed for increasing the micropropagation rate and reducing problems such as vitrification. Somatic embryo production was obtained for oak, beech, chestnut and camellia and preliminary work on automation and economic assessment was initiated.
The tasks of this research project will be taken up by the following approach:
select elite germplasm and generate stocks in vitro and in nurseries;
exchange germplasm already in vitro and harmonize procedures;
investigate ways to facilitate induction and modulation of juvenility in tissues of mature trees and cultured explants using known empirical methods,
employ well studied analytical methods so as to characterize, manipulate, and correct biochemical aspects of metabolism which present problems in propagation rate, juvenile to adult phase changing, rooting, vitrification and apex necrosis;
study all unique aspects to facilitate and improve large scale production, including interactions of above two tasks, environment, substrates, weaning, mycorrhizas and alternative regeneration systems (eg somatic embryogenesis and automation);
determine parameters for conservation of elite germplasm as seeds (Oak) and vegetative propagules by growth limitation and cryopreservation;
carry out an economic evaluation and field testing of elite material with intensive management in pilot plantations based on the concept of medium rotation systems (50 to 60 years) in comparison to models of conventional (100 to 300 year) forestry.
Funding SchemeCSC - Cost-sharing contracts
56030 Cascine Di Buti Pisa
15318 Abegondo La Coruña
15780 Santiago De Compostela
26 Bray, County Wicklow
6700 AA Wageningen
6698 Grand Halleux