Bulletin of Polessky State University. Series in Natural Sciences

Forecast of expansion of Salvinia Natans L. in Belarus

2025-08-29T12:29:35+03:00

Objective. To provide a scientifically based forecast of the expansion of Salvinia natans (L.) All. in Belarus based on a retrospective analysis of its distribution and data from population genetic studies of model populations.

Materials and methods. Generalization of archive and literary data, materials of expeditionary research, methods of molecular genetics for assessing the variability and relationship of plant populations.

Results. Changes in the distribution of the heat-loving species Salvinia natans (L.) All. from the 1950s to the present have been revealed, showing the expansion of the natural boundaries of its range in the northwestern and northeastern directions. Using molecular IPBS markers, the genetic heterogeneity of model populations in the cenoareal and insular localities has been determined, showing a large variability of natural populations. Identification of the genetic relationship between populations from different parts of the range of Salvinia natans (L.) All. shows the ways and means of penetration of diaspores of the species into newly developed territories, demonstrating the mixing of the gene pool in expansive populations through ornitochory.

Conclusion. The obtained data allow us to predict a more active spread of Salvinia natans (L.) All. in the western part of Belarus, where expansive populations that have penetrated into the Shchara River basin have a relatively high adaptive potential. In the eastern part of the country, further spread of the species in the northern direction is unlikely, which is due to both the hydrographic features of the territory and the genetic parameters of the studied populations.

Quality of canned alfalfa feed depending on the phase of plant vegetation and storage method

2025-08-29T13:55:08+03:00

It has been established that for the preparation of canned feed, the optimal option is one in which alfalfa is harvested in the stalking phase and dried to a dry content of about 40%. This provides an increased concentration of exchange energy and crude protein. Harvesting feed at a later stage of vegetation and using such a technological method as mowing into a swath increases the time of wilting and leads to significant losses of all nutrients in the feed. The effect of storage methods (trench, polymer packaging) on the energy and protein nutritional value of canned feed was studied.

Spectrophotometric method for counting the number of cells and determining dry biomass of the algae Porphyridium purpureum

2025-08-29T15:20:15+03:00

In the modern world, algae are widely used in various fields due to their unique biochemical composition and ability to grow quickly under controlled conditions. Red algae, including Porphyridium purpureum, are also one of the objects of algobiotechnology. However, when cultivating it, classical labor-intensive methods are often used to control growth parameters.

This study assesses the possibility of using the spectrophotometric method as an alternative to classical methods for monitoring cell growth in suspension during cultivation. Linear growth graphs were plotted, correlation and determination coefficients, the significance of regression equations and its coefficients at different wavelengths were determined, reflecting the relationship between such parameters as the number of cells and absolutely dry biomass and the optical density of the Porphyridium suspension. It was found that to determine the number of cells, the opticaldensity of the suspension should be measured at a wavelength of 630 nm and use the equation: Number of cells (million cells/ml) = 13.0821 × OD630– 1.3845. To determine the absolutely dry biomass, the optical density of the Porphyridium suspension should be measured at a wavelength of 750 nm, and for the calculation use the equation: ADB (g/l) = 3.9256 × OD750– 0.7230.

Effect of orthophosphate level in nutrient medium on Pinnularia diatome culture growth and intracellular protein content

2025-08-29T16:33:44+03:00

Exclusion of orthophosphate from the Tamiya nutrient medium caused inhibition of Pinnularia diatome culture growth, accumulation of intracellular protein and cell death on the 17th day.

In the range of orthophosphate concentrations of 2.2•10–8–2.2•10–5 M, the concentration dependence of the biomass dynamics was complex. Even a decrease in the concentration of orthophosphate in the nutrient medium was not always accompanied by inhibition of culture growth, and in some cases its level was not inferior to the original Tamiya medium (control). Perhaps this reflects the mechanisms of cell adaptation, and not the toxic effect of the phosphorus salt.

Despite the linear dynamics of the increase in intracellular protein content, at all concentrations of orthophosphate in the nutrient medium, the protein level was significantly lower than the control variant. Perhaps this reflects a non-optimal ratio of the phosphorus level with other components of the nutrient medium, primarily the nitrogen source.

Structure of complexes of bumblebees – visitors of clover flowers

2025-09-22T12:48:39+03:00

The paper presents an analysis of the structure of pollinator complexes of pollinators of clovers (Trifolium hybridum, T. repens, T. pratense) where the greatest abundance is demonstrated by bumblebees of the species B. lapidarius, B. terrestris and B. pascuorum. This is the main group providing pollination of these plant species.

Molecular genetic approaches to diagnostics of aphids of the genus Brachycaudus, forming mixed colonieson plants of the genus Prunus in Belarus

2025-09-23T16:27:15+03:00

Nucleotide sequences of the COI gene fragment were deciphered for the aphids B. divaricatae and B. prunicola of the fauna of Belarus. Restriction maps were constructed for aphids for B. prunicola, B. divaricatae and B. cardui taking into account all identified COI haplotypes. 4 restriction enzymes were selected to detect B. prunicola, 1 enzyme for B. divaricatae and 1 enzyme for B. cardui. 2 enzymes were identified that cut only the nucleotide sequences of the COI gene fragment of the aphids B. divaricatae and did not cut the nucleotide sequences of the COI gene fragment of the aphids B. cardui and B. prunicola.

Primary data on infection of bumblebees (Bombus Terrestris) with nosematosis (Nosema Bombi) in Belarus

2025-09-24T15:45:55+03:00

The paper presents studies of nosematosis (Nosema bombi) in bumblebee families of Bombus terrestris in some regions of Belarus, which showed an average level of infection. The data indicate the need for a broader study of this problem.

Characteristics of protein heterogeneity of the Ericaceae family representatives and the markers of plant tissue dedifferentiation identification

2025-09-24T16:10:38+03:00

The Ericaceae family berry plants (lingonberry) screening for the secondary metabolites high concentration (including arbutin) was carried out. The most promising varieties for the biologically active substances obtaining by the biotechnological methods were selected.

Proteomic analysis of lingonberry, as well as the callus cultures initiated from different types of tissue (leaf, stem) was carried out for the first time. The proteomic maps were obtained. The proteins that claim to be specie’s and cultivar’s markers were identified. The biochemical markers of plant and callus culture development were identified.