Melun et al. (2016) - Poster scientifique - Productivité de clones d'Eucalyptus gundal tolérants au froid
Productivity in various pedo-climatic conditions of cold-hardy Eucalyptus clones developed by FCBA for plantation forestry in southern France.
Fourth international conference of the IUFRO unit 2.09.02 (somatic embryogenesis and other vegetative propagation technologies) on “Development and application of vegetative propagation technologies in plantation forestry to cope with a changing climate and environment”, September 19-23, 2016 (La Plata, Argentina), poster 45.
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Ce travail repose sur un dispositif expérimental de 75 essais répertoriés dans la base BAOGREFF de FCBA.
Melun F, Nguyen The N, Alazard P, Fraysse J.-Y, de Boisseson J.-M, Fauconnier T, Rousseau J.-P., Périnot C., Canlet F., Reymond I., Durandeau K., Debille S., Harvengt L., Bailly A., Trontin J.-F.
Développements FCBA, Pôle Biotechnologie et Sylviculture Avancée
FCBA (formerly AFOCEL) is developing researches and a long-term breeding program of Eucalyptus species since the seventies. The program includes both traditional breeding and already operating biotechnological inputs such as clonal micropropagation, cryopreservation and DNA fingerprinting. Significant developments in Eucalyptus genomics are also ongoing in the frame of partnerships at the national and international levels towards increased knowledge about genes involved in cold-hardiness, growth, development and wood properties of interest for customers (pulp industries, biomass production).
The main objective is to select and deploy fast-growing varieties in clonal plantation forestry that are well-adapted to the various pedo-climatic conditions found in southern France from oceanic to more Mediterranean and arid conditions. One critical issue for breeders is to improve cold-hardiness of new varieties developed for foresters to cope with erratic severe winter frost. Selected Eucalyptus species for this program, mostly E. gunnii and E. dalrympleana, originated from the mountainous regions of their natural distribution area in Australia, especially Tasmania. E. gunnii was identified as one of the most appropriate tested species for cold hardiness whereas E. dalrympleana has less tolerance but better growth behaviour. Breeding was focused on E. gunnii and the E. gunnii x E. dalrympleana hybrid species (E. gundal) using well-selected provenances.
The best selected hybrids clones for both good growth and significant cold-hardiness (up to -12°C at a 50% cutoff threshold for damages) were successfully introduced in vitro for conservation purposes (including cryopreserved collections), reactivation or maintenance of organogenic capacities (especially rooting ability) and rapid initial vegetative propagation through micropropagation. In vitro rootstocks are then implemented by commercial forest nurseries (e.g. Forelite) to form large stool beds for the production of cuttings from selected varieties. Following this strategy, around 2000 ha of pilot clonal plantations have been established (100-150 ha/year), mainly for the purpose of short rotation coppices (3 rotations of 10-12 years).
In this presentation we specifically reported on the productivity at ages 4 to 13 years of 1 control (FCBA-121) and 2 commercially available FCBA E. gundal clones (FCBA-208, FCBA-645). These varieties have been tested at various field plots (75 stands) in southern France divided into 3 large pedo-climatic areas from East to West (Mediterranean, transitional oceanic and oceanic) with corresponding rainfalls in the range of 500-1500 mm/year. A map of putative development zones for eucalypts has been established based on pedo-climatic data, especially the frost constraint. Considering a combination of all 3 rotations, an East-West productivity pattern is observed for these E gundal varieties at age 10-12 years, from 10-15 t/ha/year in the Mediterranean climatic zone to 20-30 t/ha/year and even up 35 t/ha/year in most favorable conditions of the oceanic zone. Productivity is mainly associated with water availability and soil quality. E. gundal hybrids are capable of regulating water use both positively (conditions with good water availability) or negatively (drought stress)