Research

The process of plant somatic embryogenesis allows the acquisition of a large number of genetically identical individuals. That fact is used in practice to obtain a rich progeny from a minimal number of seeds. At the same time, somatic embryogenesis is an ideal system for studying the early stages of plant development. Somatic embryogenesis starts by the derivation of embryogenic culture, mostly from zygotic embryos. Embryogenic cultures are cultivated in vitro on precisely defined media, whose composition determines further development of somatic embryos. In conifers the whole process consists of five basic steps - induction of embryogenic culture, proliferation, maturation of somatic embryos, desiccation and germination.

Polyamines (PAs), low molecular mass polycations, are ubiquitous cell components that are essential for normal growth of both eukaryotic and prokaryotic cells. Most of the biological functions of PAs can be explained by their polycationic nature, which facilitates interactions with anionic macromolecules (such as DNA and RNA) and negatively charged groups of membranes. They are implicated in a wide range of biological processes including cell division and growth, morphogenesis and differentiation and responses to biotic and abiotic stresses. The most abundant PAs in plants are putrescine (Put), spermidine (Spd) and spermine (Spm).

• Hebrew University, Institute for Drug Research, Jerusalem, Israel 
• Forestry and Game Management Research Institute, Strnady, Czech Republic
• Forestry and Game Management Research Institute, Department of Reproductive Sources, Research station Kunovice, Czech Republic

• National Institute for Agricultural Research (INRA), Unit for Improvement, Genetics and Forestry Physiology (UR 0588), Orléans, France
• Institute of Plant Genetics and Biotechnology of the Slovak Academy of Sciences, Nitra, Slovakia
• Department of Experimental Plant Biology, Faculty of Science, Charles University, Praha, Czech Republic
• Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
• Department of Crop Sciences and Agroforestry, Faculty of Tropical AgriSciences, Czech University of Life Sciences, Praha, Czech Republic
• Department of Forest Ecology, Faculty of Forestry and Wood Science, Czech University of Life Sciences, Praha, Czech Republic

Annotation:

The aim of the project was to evaluate the alterations in polyamine metabolism and in the levels of hydroxycinnamic acids, flavonoids and stilbenes in the stress response of somatic embryos of Norway spruce to drought and high temperature. The determined contents of abscisic acid and auxin contributed to understanding the abscisic acid-auxin cross-talk in the response to stress. The extent of lipid peroxidation (as indicated by MDA levels) in stressed somatic embryos was also investigated. Histochemical tests for the presence of polyphenolic substances on embryo sections after the exposure of somatic embryos to UV-B completed the biochemical analyses.

Cultivation and genetic factors affecting efficiency of conifer somatic embryogenesis.

MŠMT, 2000-2004, Martin Vágner

Annotation:

The aim of the project was to evaluate the alterations in polyamine biosynthetic enzymes and polyamine contents and the levels of hydroxycinnamic acids and flavonoids after the exposure of embryogenic tissue cultures of Norway spruce to UV-B radiation. Histochemical tests for the presence of polyphenolic substances (with UV-B protecting character) on embryo sections completed the biochemical analyses.

Výzkumný záměr podporovaný AV ČR

AV0Z50380511 - Mechanisms of regulation of plant growth and development on the level of cells, organs and whole organisms: physiological, genetic and molecular bases

(2005 - 2010)

Annotation: 

The overall goal of the project is to determine the factors responsible for the inefficiently of existing, pre-sowing treatments so that beechnut germination and subsequent emergence of beech germinants can be improved. The results will be used to develop protocols for providing better and more economical use of beechnuts including field emergence and for obtaining sufficient quantities of seedlings for reforestation.

Annotation:

The aim of the project is to evaluate the response of Norway spruce somatic embryos to abiotic stresses. Somatic embryos will be exposed to different desiccation treatments (high temperature and decreased humidity) and to different doses of UV-B radiation. The alterations of activities of polyamine biosynthetic enzymes and contents of polyamines, abscisic acid (a key endogenous messenger in a plant's response to stresses) and the extent of lipid peroxidation will be evaluated in somatic embryos cultured in stress conditions.