ИСТИНА

Growing Arabidopsis in Petri dishes under full illumination of the root and shoot is the common and well accepted experimental method in plant biology. It is also well known that root of the most plants should grow in darkness so there is an opinion that light is a stress factor for the root growing. Abiotic stresses could cause аn acceleration of the growing to escape the problem or an inhibition of root growing in particularly. Light promote root growing, but salt stress inhibits it. The idea of the present work was to compare the involvement of these two stress abiotic factors for Arabidopsis growing in vitro. We have measured primary root growth and also compared germination rate and survival time of plants growing continuously on 0, 50, 100,150 mM NaCl. As object of research phya, phyb, phot1, phot2, cry1, cry2 mutants (background Col-0) were used. The more prominent differences between wild type and mutants have been found under 150mM NaCl in media. Mutants on photoreceptors have shown definitely longer survival time than wild type. We can conclude that photoreceptors not only involved in primary root growth and germination under salt and light stresses, but can influence salt tolerance of the adult plants as well.