Vol 46, No 3 (2019)

The component composition and content of mycotoxins in perennial legumes of the genera Lathyrus (L. pratensis L., L. vernus (L.) Bernh., L. sylvestris L., L. niger (L.) Bernh., L. japonicus Willd., L. palustris L.) and Vicia (V. cracca L., V. sepium L., V. sylvatica L.) selected from natural biocenoses were studied. The greatest intensity of accumulation and diversity of fungal metabolites were found in meadow peavine, and the lowest intensity was in the peas. The general features and interspecific peculiarities of the mycotoxin profile in the plants of the genera Lathyrus and Vicia, as well as its variability in meadow peavine and cow vetch within different periods of vegetation, are discussed.

The expression of the Ams-1, Pel-1, Eng-1.4, Cle, VAP-1, SPRYSEC-1, Tpx, and Gpx genes was studied in Globodera rostochiensis juveniles at early stages of the life cycle. Low gene activity was registered in juveniles inside the cyst. It was established that the transition to active life is accompanied by transcriptome activation. It was found that when susceptible plants (characterized by slow development of protective reactions) act as a host, gene expression is increased in the juveniles depending on the stage of development; this provides a successful passage of the nematode life cycle. A decreased gene transcription is registered in the juveniles in the case of plants treated with short-term temperature drops (DROP treatment); this can lead to the suppression of nematode development.

Analysis of the aerobic heterotrophic component of bacterial communities from samples of poorly studied ancient ice wedge from the Mamontova Gora section (Central Yakutia), was carried out. The abundance of colony forming cells (CFU) of aerobic heterotrophic bacteria detected by plating of the thawed samples onto an agar nutrient media varied within 10³‒10⁴ CFU/mL. At the same time, the total number of intact cells was only 1−2 orders of magnitude higher. The taxonomic position of bacteria was determined by analysis of the 16S rRNA gene sequences. These bacteria were represented by three phyla: Actinobacteria, Firmicutes, and Proteobacteria. The temperature growth range of 8–20°C, which is characteristic of psychrotolerant bacteria, proved to be a specific physiological feature of the isolated strains. Most bacteria were found to be sensitive to a wide range of antibiotics.

Seeds of two orchid species from the Dactylorhiza genus (D. baltica and D. maculata) collected in Belarus and in Russia and placed for long-term preservation into liquid nitrogen in the cryobank of the Timiryazev Institute of Plant Physiology were studied. The complex quality evaluation of collection specimens was carried out by using the seed viability rating and also by their morphometric and physiology characteristics. It was shown that comprehensive study of seed specimens collected from different habitats at different times may be synchronized by applying a cryopreservation technique and in vitro method for plant material cultivation.

This article summarizes data on the influence of microwave radiation on the metacercariae of opisthorchids Opisthorchis felineus (Rivolta, 1884) and the larvae of three Trichinella species (genus Trichinella Railliet, 1895). The high efficiency of microwave radiation on the viability of larvae of these species is shown. Even short-term exposure leads to complete death of the larvae of the helminths in the muscle tissue. The mechanism of the effects of microwave irradiation on the larvae and the possibility of using household microwave ovens for preventing these parasitic diseases is discussed.

The cognitive-stimulating, neuroprotective effects of promising fluorinated tetrahydrocarbazole derivatives (CA-7043x and CA-7050x) on the hippocampus-dependent memory of outbred mice (CD1) and transgenic Tg6799 mice, as well as their effect on anxiety, locomotor activity, and orienting-exploratory behavior of animals, were studied. It was found that both compounds have a pronounced cognitive-stimulating effect on CD1 mice, but do not show neuroprotective effects on memory support in Tg6799 mice. It is noted that, in the open-field test, the CA-7050x compound has a positive effect on the orientating behavior, and the CA-7043x compound has a positive effect on the exploratory response in the nontransgenic control.

The development of bacteria, phytoplankton, zooplankton, and microperiphytic organisms in artificial ecosystems, such as microcosms with aquatic plants, depressing algae (water soldier Stratiotes aloides L.), and plants not possessing a significant impact on them (arrowhead Sagittaria sagittifolia L.), was evaluated. It was shown that the zooplankton biomass did not decrease among water soldiers, despite the fact that the concentration of phytoplankton pigments was 2–3 times lower. The number of euplanktonic Cladocera has not declined, and the number of littoral and phytophilic Cladocera increased, but the number of Diaptomidae was lower. It is assumed that a large zooplankton biomass was produced by the use of bacteria and protozoa as an additional power supply to the algae. The share of zooplanktonic species consuming bacteria increased in microcosms with arrowhead. The number of predators increased and trophic relations between zooplankton and microperiphyton became closer in experimental systems with the plants of both species.

It is noted that baculoviruses and their insect hosts are convenient objects for studying relationships in the pathogen–host system. It has been established that interest in viruses of this family is associated with their use as molecular vectors for introducing and expressing foreign genes in insects and cell cultures. It has been noted that, in recent decades, using a number of molecular biology methods, a whole series of fundamental data has been obtained on the diagnosis of hidden viruses in insects and evidence of their vertical transmission. Information is provided on the role of vertical transmission in the system of relationships between baculoviruses and their insect hosts at various ecological levels.