CORDIS oferuje możliwość skorzystania z odnośników do publicznie dostępnych publikacji i rezultatów projektów realizowanych w ramach programów ramowych HORYZONT.
Odnośniki do rezultatów i publikacji związanych z poszczególnymi projektami 7PR, a także odnośniki do niektórych konkretnych kategorii wyników, takich jak zbiory danych i oprogramowanie, są dynamicznie pobierane z systemu OpenAIRE .
Rezultaty
Multiplication of a given genotype for the production of good quality forests is a practice in forest management, mostly achieved by multiplying selected trees vegetatively via cuttings. An alternative and more efficient procedure for the mass production of selected genotypes would be the application of in vitro somatic embryogenesis. The induction of embryogenic cultures from somatic tissue and the procedure of in vitro embryo production are artificial processes, which could result in stress/adaptation response of the cells. These circumstances may induce mutation events in the genome, therefore the investigation of the genetic stability is crucial in the mass production of trees.
The developed system applies microsatellite regions as reporter regions to monitor mutation event in the genotype of the embryo producing plant callus tissue. These results will be published. The results will be the basis for further research to elucidate, which gene activities could lie beyond genetically unstable genomes. This will result in a patented molecular test system for detecting unstable genomes. Such results could increase user audience in science and technology fields as well.
More than 850 embryonic cell lines from 14 full-sib families of the Landes population of Pinus pinaster cryopreserved. Somatic embryo plants from those families established in greenhouses or nurseries.
For the first time, a large number of embryogenic cell lines from elite families of the Landes population of P. pinaster have been initiated, stabilized and cryopreserved for long-term conservation. Somatic embryo plants from over one hundred genotypes have been regenerated and successfully transferred to nurseries. The procedures were strikingly distinct from those used for P. sylvestris. Growth characterization showed that the somatic embryo plants function properly, like ordinary plants. Their production of well performing cuttings without any defect like plagiotropy opens the way to a huge decrease in the cost of plant production through somatic embryogenesis.
The material is of very high genetic value (being full sibs from parents selected from the breeding population, i.e. we have precise and full knowledge of genetic origin) and particularly adapted to the Northern part of the distribution range of P. pinaster. (Only such frost resistant material is authorized for commercial deployment in France, Iberic provenances being prohibited due to frost sensitivity having caused extensive damage to the forest in the past.) It will speed up the breeding program, allow long-term conservation of genetic resources and accelerate deployment of superior material. It will allow highly interesting research on genetic diversity of plants propagated through somatic embryogenesis and will provide material for investigation of genotype-specific optimisation of techniques.
Some remarkable lines will be used as references in transgenesis and physiological experiments. A large commercial nursery and an industrial pulp and paper company are interested in further demonstrating the performance of the system in order to validate its economical interest. Communication to industrial and tree planters will be organised. Several plots for demonstrating this material to the potential users will be established and experimental plots will allow us to monitor the long-term behaviour of the material. When old enough, the trees will be subjected to wood and paper quality analysis.
More than 1400 embryogenic cell lines from 21 half-sib families of Pinus pinaster were established using a protocol optimised for Portuguese maritime pine genotypes. The genotypes were obtained from selected mother-trees of Pinus pinaster used in the Portuguese breeding program. The optimal developmental stage and composition of the basal medium were identified.
Seventy-eight lines were cryopreserved following a cryopreservation protocol allowing for maximal survival and growth rate after thawing. In this protocol, the osmotical conditions, as well as cell density and post-thawing treatments were optimised for our genotypes. Over 300 embryogenic lines have been subjected to maturation and the recovered embryos germinated. Somatic embryo plants from 8 OP families of Pinus pinaster have been transferred to ex vitro conditions, acclimated and established in the greenhouse.
The protocol used worked for a number of important genotypes and can be applied together with conventional vegetative propagation in the Portuguese maritime pine breeding program in collaboration with the National Station of Forestry. The propagation system may be further exploited by the private sector (Portucel, Aliana Florestal, Centro Pinus). The plants to be established in the experimental field, supervised by Centro Pinus, will be critical for demonstration purposes for pine growers and industrials.
A balanced nitrogen supply is critical for somatic embryo development and regeneration of somatic embryo plants. However, very little is known about nitrogen metabolism at early stages of embryonic development, including the function of key genes, how these genes are expressed and how they are regulated. A molecular analysis of genes/enzymes involved in nitrogen metabolism has been performed in somatic and zygotic embryos of Pinus sylvestris and Pinus pinaster at selected stages of their development. Specific genes have proved to be good markers correlating their expression levels with the viability of the embryos as well as the proliferation ability of the cell lines. Gene expression patterns associated with fundamental processes such as chloroplast or vascular development were identified. Enhanced efficiency for nitrogen recycling can result in better exploitation of nutrient resources, improved efficiency of photosynthetic cells and faster plant growth. Therefore, studies on primary metabolism have been used to analyse the functional competence of regenerated somatic embryo plants.
Results generated in the frame of this project are of major interest to understand early steps of development not only in pine but also in other conifer species of economic and ecological interest. The basic knowledge on nitrogen metabolism will be utilised by other research groups in the field and may have practical applications to support improved methods for propagation of conifers.
This result covers plant materials derived from half-sib P. sylvestris families in Sweden and full-sib P. sylvestris families in Finland. More than 250 cell lines established from 15 half-sib families and 150 cell lines from 31 full-sib families were cryopreserved and stored in liquid nitrogen. Embryogenic cultures from 11 half-sib and 4 full-sib families were thawed, re-established and somatic embryo plants were regenerated. More than 900 plants from the half-sib and about 300 plants from the full-sib families were acclimatized. About half of them have been established in nurseries and the rest are under way.
The plants will be planted in demonstration trials. They will guide nurseries and forest owners (private and companies) in evaluation of propagation method, plant type and for selection of valuable genotypes. Cryopreservation enables safe and rapid propagation of selected clones immediately after the field test period. Use of somatic embryo plants in the breeding program will result in reduced time for completing a breeding cycle and higher selection intensity.
Cryopreserved, tested and selected genotypes will be a resource for increasing wood production and improving wood properties. In addition, scientists in physiology and genetics can use them for basic studies.
The protocol developed for production of somatic embryo plants of Pinus sylvestris and P. pinaster involves:
- Choice of plant material;
- Growth on culture media of specific compositions;
- Cryopreservation;
- Germination and;
- Ex vitro establishment.
The protocol will be of great use for companies/institutes working with forest tree breeding, plant production and gene conservation as well as for nurseries.
The advantages are the following:
- A great number of plants can be obtained in a short time.
- Somatic embryos can be cryostored, keeping the vegetative propagation ability of the genotypes.
- Somatic embryos can, with high flexibility and large realised genetic gains, connect tree breeding programs with vegetative propagation programs.
To meet the increasing demand for forest products whilst setting off large areas for natural forests, productivity in the production forest must increase. High productivity requires use of improved plants with known value. Tested and vegetatively propagated plants will serve this requirement best. Somatic embryogenesis is an attractive method for vegetative propagation of forest trees. Somatic embryo plants are on the market in USA and Canada and we foresee the same development in Europe when the somatic embryo plants have been tested in field trials.
Further adaptation and automatization of the methods are needed in order to reduce the cost and adjust the method for more genotypes. In addition, somatic embryogenesis is a valuable tool for studying and teaching embryology.
Wyszukiwanie danych OpenAIRE...
Podczas wyszukiwania danych OpenAIRE wystąpił błąd
Brak wyników