A. I. Shmakov

The phenomenon of endopolyploidy in some species of the Chenopodioideae (Amaranthaceae)

Abstract The flow cytometry-based DNA analysis of leaf blade cells from 18 species and one subspecies of the subfamily Chenopodioideae (Amaranthaceae) revealed three histogram peaks typical for the presence of endopolyploidy. Although endopolyploidy is the most common ploidy in plants, this phenomenon was not previously found in such a large number of wild species of Chenopodioideae. It was also so far not reported for Suaeda, Dysphania and Oxybasis. Neither analysis of ploidy level by light microscopy nor flow cytometry revealed endopolyploid nuclei in root meristems. Endopolyploid cells were found in leaf blades and stems in all samples. The highest level of endopolyploidy was found in Suaeda. We also found that endopolyploidy is usually found in diploid species of Chenopodium, Dysphania, Oxybasis and Suaeda. The endopolyploidy from hexaploid samples of Suaeda tuvinica and octaploid Suaeda sibirica was not revealed.

About species independence of Polystichum subtripteron Tzvel

The article discusses the species independence of Polystichum subtripteron Tzvel. The spore structure and size of 2 closely related species – P. subtripteron and P. tripteron were studied. Morphological differences of fronds fit into the overall range of variation; there are no differences in the spore external structure. DNA fragment analysis (ISSR) of 19 specimens of both species was conducted. Fragment analysis revealed no significant differences between P. tripteron and P. subtripteron samples. All differences are probably due to genetic isolation of populations, and the island populations are closer together. On the basis of the research we conclude that in the Far East one species Polystichum tripteron grows, and P. subtripteron can be considered its synonym.

Pathogenicity of Simplicillium lanosoniveum to Coccus hesperidum

Simplicillium lanosoniveum isolate SSBG2 was isolated from the diseased C. hesper collected from Schefflera octophylla in greenhouse of the South-Siberian Botanical Garden, and identified based on morphological observation and ITS region analysis. The infected plants were inoculated with conidial suspension of the isolate SSBG2 in concentrations 1.0*10 5 /mL. It was showed that after inoculation the C. hesper female adults were more vulnerable to infection. Larvae are affected to a lesser extent. The mycelium grows under the scale and cause the death of the insect. It was indicated that S. lanosoniveum had high infectivity against C. hesper . Infection symptoms appeared on day 7 after the inoculation, the infection reached the peak on day 20. Our study provides a new isolate that affects the Coccus hesperidum .

Addition to the flora of Altai. III.

For the territory of the Altay Mountain are the location of new fern species belonging to families of Athyriaceae, Cryptogrammaceae, Cystopteridaceae, Dryopteridaceae, Hypolepidaceae, Onocleaceae, Polypodiaceae, Thelypteridaceae, Woodsiaceae.

PLOIDY LEVEL AND RELATIVE NUCLEAR DNA CONTENT IN THE PLANT CELL AND TISSUE CULTURE IN VITRO

We presented results of variations in the ploidy level and the genome size of the R. acetosa regenerants. These regenerants was obtained by indirect and direct morphogenesis in in vitro culture. Explants were prepared from seedlings on the three-leaf stage of plant development. More than 100 explants were used to stimulate the indirect and direct morphogenesis. Mesophilic explants were cultured on the MS nutrient medium containing auxin to callus proliferation (2 mg/L NAA, 1 mg/L BA). Cultivation of the callus was maintained for 4 weeks followed by an indirect morphogenes. Indirect morphogenesis stimulated on the MS medium with cytokinin and gibberellic acid predominance (0.5 mg/L BA, 0.2 mg/L GA3). Direct stimulate morphogenesis from the apical meristem of seedlings on nutrient media with a predominance of cytokinins (1 mg/L BA, 0.25 mg/L NAA). Rhizogenesis have stimulated by transferring of the regenerants to the ½MS medium supplemented with 0.2 mg/L of NAA. Research of a ploidy level and genome size was performed by flow cytometry used propidium iodide staining with Vicia faba cv “Innovec” (2C=26.90 pg) as internal DNA standard. We calculated the relative DNA content (2C) for R. acetosa equal to 6,98 pg. Cytogenetical analisis showed that the maximum genome size variation recorded for regenerants obtained through the indirect morphogenesis. Variations in the genome size of the regenerants obtained by direct morphogenesis deviates from the control group to 0.30 pg (2С=7.28 pg) and after indirect morphogenesis to 1.04 pg (2С=8.2 pg). Cytogenetical analysis of the regenerated plants showed the presence of different somatic chromosome numbers ranging from 2n = 14 to 2n = 28. The relative DNA content of tetraploid forms was 11.87 pg. In our study was shown, that the most effective method of plant conservation in the in vitro culture is a direct morphogenesis. Analysis of the relative nuclear DNA content and chromosome counts of regenerants obtained by indirect morphogenesis from the callus cultures showed significant variations in the DNA content, as well as the appearance of polyploid forms. Therefore, long-term cultivation of callus cultures increases the probability of genomic aberrations, which reduces the stability of the plant genome.

SYNOPSIS OF THE GENUS ACTINIOPTERIS LINK (PTERIDACEAE)

The synopsis of the genus Actiniopteris Link is presented in the article. Localities are exactly pointed for all species. The original key for determination of Actiniopteris species has been developed.

SPORE MORPHOLOGY OF POLYPODIUM ALEUTICUM A.E. BOBROV (POLYPODIACEAE) AND RELATED SPECIES

Spores of type specimens of Polypodium aleuticum A.E. Bobrov are studied by SEM-method. The morphology of the spores has been studied and described for comparative purposes. The results showed characteristic features of P. aleuticum exospores different from P. glycyrrhiza D.C. Eaton, which gives the basis for acknowledgment the independence of the investigated species.

STUDY OF GENOME SIZE REPRESENTATIVES OF THE GENUS POTENTILLA L. (ROSACEAE JUSS.)

In our study, 15 representatives of the genus Potentilla L. were analyzed to obtain the relative DNA content and monoploid genome size in the seeds by flow cytometry method. For these Potentilla species, except P. argentea and P. norvegica , DNA content and genome size are revealed for the first time. As a result, the following data were obtaining: representatives of the older section Desertae are diploids with the large monoploid genome size. The genome of P. asiatica (Chrysanthae section) are decrease up to 0.35 pg, while the ploidy is increased to 4. Representatives of the Multifidae and Supinae section are presented with tetra- and hexaploid species with the 0.3 pg of the monoploid genome size. In section Tanacetifoliae are observed a further decrease of the genome size, representatives basically tetraploids. Thus, in the genome size evolution of a Potentilla genera are observed the increase of ploidy with significant reductions in monoploid genome size. This fact proves the general theory of genome evolution of angiosperms, directed towards its reduction. Linear regression analysis was showed a positive correlation between chromosome number and genome size of the representatives of the Potentilla genera. This suggests that between genome size and the number of chromosomes in Potentilla species are linear dependence. Pearson correlation analysis confirmed this result: the correlation coefficient is 0.97 at P<0.05.

An effective way to carry out mass in vitro propagation of Potentilla alba L

Despite the plant’s extensive area of distribution, Potentilla alba L. natural resources are scarce and cannot meet the modern needs of the pharmaceutical industry. Because of the mass preparation of medical raw materials by using P. alba , it entered into the list of rare and endangered species plants of the Red Data Book of the Republic of Belarus. This plant is not represented in the wild flora of Western Siberia, but there is a great need for developing a method for the mass propagation of P. alba using in vitro culture in order to obtain a high-quality planting material. At the explant stage, the technique of the P. alba introduction into in vitro culture is developed. This paper reveals the morphogenetic features of the development of P. alba explants of different types and the regenerative capacity of the tissue culture. At the micropropagation stage, the optimum culture media and the growth conditions for the regenerated plants are selected. At the stage of test-tube plants rooting and transferring them into ex vitro conditions, the most effective means of adaptation to non-sterile conditions in hydroponics are proposed.

Possibilities of de novo transcriptome sequencing in pylogenetic research on an example of Taraxacum officinale (Asteraceae)

As a result of the research we obtained a cDNA library, sequences and carried out de novo assembly and functional annotation of the transcriptome of systematically complex, almost cosmopolitan Taraxacum officinale . Systematics of the species is complicated because of separation of many microspecies and intraspecific taxa, which may be explained by the presence of ploidy races, the phenomenon of apomixis and significant polymorphism. Attempts of separation of microspecies and closely related species based on sequencing of chloroplast and nuclear DNA fragments, did not give acceptable results. We have made the first attempt to analyze the transcriptome for understanding the genome evolution of agamospermous-sexual complex of the species. A total of 84440 reads were obtained with a total 31,540,710 bp. As a result of the de novo assembly, we obtained 13902 contigs, with an average GC content equal to 38.1% and a maximum length of 5255 bp. In total, we received 3798 annotated genes. According to the functional annotation based on sequence homology, 2687 contigs were attributed to biological processes (19.32%), 3299 – to molecular functions (23.7%), 2157 – to the cellular component (15.51%) and 7497 contigs – with unknown functions. In the first category “single-organism cellular process”, “response to stimulus”, “photosynthesis-light reaction”, “oxidation-reduction” and “translation” have dominated. In the category of molecular function “nucleic acid binding”, “hydrolase activity”, “transferase” and “oxidoreductase” activities have dominated. In the cellular component category “integral component of membrane”, “chloroplast thylakoid membrane”, “photosystems” and “nucleus” have dominated.