in vitro

Lipopolysaccharides are compounds of bacterial origin that have biological activity against plants, animals and humans. This work provides information on the preparation and characterization of the properties of modifi ed lipopolysaccharide derivatives of the rhizosphere bacterium Ochrobactrum cytisi IPA7.2. Deacylation has been carried out using alkaline hydrolysis, followed by chromatographic separation of the fractions. O-deacetylation of O-polysaccharide led to a 2-fold increase in the extinction of the products of the phenol-sulfuric acid reaction.

Saratov Scientific School by Biology and Genetics of Plant Reproduction Systems was formed under the leadership of Doctors of Biology S. S. Khokhlov and V. S. Tyrnov. Most of the unique research was performed in the Laboratory of Radiation and Experimental Genetics, established in 1958. Later it was transformed into the Department of genetics and reproductive biology of the Saratov State University Botanical Garden. Over the past 60 years, Saratov scientists have made a significant contribution to the development of fundamental and applied science.

The article is focused on studying of cytoembryological preconditions of polyembryony in the not pollinated ovary of the apomictic maize line АТ-1 under in vitro and in vivo conditions. For an assessment of a nutrient medium role in polyembryony induction a relative analysis of the embryo sacs in cultivated in vitro and native plants ovaries has been lead. Dynamics of formation in them an apomictic twin proem- bryo is traced.

The research of extreme low (10°С) and high (37°С) temperatures influence under in vitro conditions on phenotypic display of three mutations in Nicotiana tabacum L. with of a certain morphological type domination was conducted. The BG-141.4 line is character- ized by low-cellular embryo sacs formation, in the SG-27/4 line the trait of the increased number of nucleus and cells in embryo sacs exhibits, the line М-3 differs by high frequency of cenocyte low- cellular embryo sacs.

Many modern selection technologies are based on the use of haploid plants as a starting material. The spontaneous frequency of haploid development is very low (0.01–0.1%). In this regard, the creation of plant forms with increased frequency of parthenogenesis is important. The collection of corn lines with an increased frequency of haploid plants in the progeny was created at the Department of Genetics of the Saratov State University. High costs are required for maintain of a plant collections in the field.