Том 53, № 3 (2019)

The impact of exogenous cytokinins (kinetin, zeatin, 6-benzylaminopurine, and N6-2-isopentenyladenine) on the pattern of Dryopteris filix-mas (L.) Schott spore germination, gametophyte growth and morphology in vitro have been studied. It was found that all studied cytokinins significantly retarded spore germination, inhibited gametophyte growth, caused deformations and decrease in the thallus size, and suppressed the development of reproductive structures and sporophyte growth at the concentration of 10^–5 М. The reduction of the hormone concentration to 10^–8 М stimulated the gametophyte development, induced cell divisions, particularly in the apical zone, due to which some of thalli were deformed, promoted the production of rhizoids, affected the formation of antheridia and archegonia, and slowed the sporophyte development.

Molecular-genetic research methods make it possible to identify phytopathogens with comprehensive characteristics of their hereditary material. We suggest a genotyping method based on the use of two restriction endonucleases for the cleavage of bacteria’s genomic DNA. Taq DNA polymerase added to the reaction mixture provides labeling of DNA fragments with biotinylated deoxycytosinetriphosphate (Bio-dCTP). The label is only incorporated into DNA having 3-prime recessed ends formed by the first enzyme. The second restriction endonuclease produces only blunt ends of fragments that are unable to incorporate the label. As a result of the DDSL (double digest selective label) reaction, 20–50 distinct DNA fragments are visualized on the filter, the amount and distribution of which are specific for each bacterial strain. This research was carried out using two pairs of restriction enzymes (XbaI/DraI and XbaI/Eco24I). The results indicate the same discriminatory capacity of these enzymes. Some advantage was noted for the XbaI/DraI combination, which makes it possible to detect differences in the region of longer DNA fragments in genetic profiles. The genetic profile generated by the BcuI/Eco32I pair of enzymes in Ps. fluorescens 894 was significantly different from that of Ps. xanthochlora, which could be anticipated while comparing these two species. In general, the results of genotyping agreed with the data on the origin of bacterial strains. In particular, microorganisms with the same genetic profile, D822 and D828, G399 and G400, as well as C960 and C966, were obtained from affected tubers of the same experimental field. This suggests the possibility of the contact spread of the pathogen. In some cases, the identity of strains was observed, despite their different geographic origin. This fact confirms contamination that occurred in the past during the use of the foreign seed potato.

The efficiency of in vitro fertilization and embryo transfers into human uteri is low, because approximately 50% of embryos transferred into the uterine cavity are capable to continue their development. This situation has generated the problem of early diagnosis of embryo potential at the stage preceding the selection of morphologically and chromosomally good quality blastocysts. The fertilization quality was assessed 16–18 h after an intracytoplasmic sperm injection (ICSI) micromanipulation by the presence of pronuclei using Z-scores. We examined the size and the location of pronuclei relative to the cell center, the number of nucleoli, and their distribution. The best development and, respectively, the highest implantation potential were demonstrated by embryos developed from zygotes of the Z1 category. Zygotes Z2 and Z3 also formed AA quality blastocysts on day 5. None of the fertilized oocytes forming zygote Z4 developed into a viable embryo. We have established differences in the capability to form AA quality blastocysts between zygotes of categories Z1, Z2, and Z3 and the category Z4 as well as between categories Z1 and Z3. It has been found that the highest number of embryos in which the number of the studied chromosomes corresponded to the norm was formed from zygotes of Z1 and Z2 categories, and a significant difference in the number of embryos in which aneuploidy has not been diagnosed has been found in embryos formed from zygotes of Z1, Z2, and Z3 categories compared with type Z4 zygotes.

Sugarcane is one of the most important worldwide cultivated agro-industrial crops that belong to the family Poaeceae and genus Saccharum. Prescribed study was conducted in Seed Biotechnology Lab, Center of Excellence in Molecular Biology, University of the Punjab, Lahore-Pakistan. The purpose of this study was to alter the genome of sugarcane line CPF246 with herbicide resistance gene GTGene driven by the sugar cane ubiquitin promoter and confirmation through PCR and Dot blot as well as protein expression analysis through ELISA. Results have shown the successful transformation and expression of transgenes against glyphosate resistance. This could prove a mile stone towards putting research efforts in the improvement of Saccharum officinarum for certain traits. Outcomes of this research will be beneficial in minimizing the management cost which people do bear for weed management practices. Success of this study opens new horizons to further improve other characteristics of sugarcane using genetic modification as was done in current study.

In the present study, a total of eleven low-copy nuclear gene markers were developed using transcriptomes for the plant genus Orinus Hitchc. (Poaceae), which comprises three species of grasses widely distributed in the Qinghai-Tibet Plateau. These developed markers were successfully amplified and sequenced for 90 individuals from nine populations of three Orinus species. The DNA sequences for the eleven loci ranged from 606 to 1152 aligned based pairs. Compared with four candidate DNA barcoding markers in our previous studies, the newly developed markers had a relatively higher number of parsimony informative sites than three cpDNA spacers (7–20 vs. 1–8), but slightly lower than those of the internal transcribed spacers (ITS). Hence, these novel low-copy nuclear gene primer pairs were validly useful for the study of phylogeography, phylogenetic analysis and population genetics. Moreover, they could be used in phylogeny reconstruction and speciation for a broad range of Orinus and even the entire subtribe Tridentinae.