Growth and development of representatives of the genus Rosa L. in the Stavropol Botanical Garden

Relevance. To identify the features of the growth and development of species of roses of different geographical origin, to establish the biological minimum temperatures necessary for the beginning of flowering of representatives of the genus Rosa L., to study the morphological indicators of fruits.Methodology. The research material was 12 wild roses belonging to 4 sections: Canina Crep, Cinnamomeae DC, Luteae Crep, Pimpinellifoliae DC. The research was carried out using the methods of the Main Botanical Garden, floral and geographical analyses — according to Hrzhanovsky. A caliper was used to measure the length and diameter of 10 fruits. For the analysis of statistical data, the MS Excel table processor and the integrated MATLAB mathematical package were used.Results. The article presents the results of a study of species of roses in the Stavropol Botanical Garden of various geographical origin. The study involved 12 species belonging to 4 sections. The features of growth and development of plants in new soil and climatic conditions are revealed. The dates of the beginning of the main phenological phases andtheir duration have been established: spring regrowth of shoots, budding, beginning and end of flowering, fruiting. In the studied species of roses, the growing season begins in the first — second decade of March, flowering occurs in late May — early June, the fruits ripen in August — September. The dependence of the timing of the beginning of flowering in the studied roses on the dynamics of the accumulated average daily air temperatures and the sum of effective temperatures above 5 °C was revealed. Mathematically, it was proved that the lower limit of the air temperature required for the beginning of flowering of species of roses is +16 °C, when the sum of the average daily temperature air St° = 1007.75–1069.48 °С and St эф > 5 °С = 530.75–594.75 °С are accumulated. Early flowering species of roses include Rosa foetida Herrm., R. pendulina L., R. pimpinellifolia L., late flowering — R. caudata Baker and R. corymbifera Borkh. The shortest flowering period is in R. caudata Baker, R. jacutica Juz. and R. kamtschatica Vent. Representatives of those types mostly bloom once. Their flowers are formed on biennial and more mature shoots. The flowering period is 13–23 days. Rosa rugosa Thunb. blooms again, its flowering period is extended and long — from 40 to 48 days. All species of roses form fruits. The longest fruits are in R. pendulina L., R. caudata Baker, R. rugosa Thunb., R. corymbifera Borkh. and R. canina L., and large ones — in R. rugosa Thunb., R. marretii Lev. and R. roxburghi Tratt.

Optical properties of honey: FTIR spectroscopy and refractometry

115 samples of honey of various botanical types, geographical origin and harvest year (2019– 2021) were analysed using attenuated total reflection infrared spectroscopy of impaired total reflection, refractometry and biochemical analysis. Initial honey samples in liquid and crystallised states were investigated. Crystalline D-glucopyranose (glucose), D-fructopyranose (fructose), their 40% solutions and invert sugar were used as auxiliary substances. Biochemical analysis was used to determine the glucose content in honey samples. Based on the obtained data, a relationship between the results of biochemical analysis and refractometry (refractive index, the content of invert sugars, humidity) was established. We deduced equations that allow the content of glucose and fructose in honey to be evaluated by the refractive index. Studying honey by IR spectroscopy showed that all investigated samples, regardless of the botanical and geographical origins, can be classified into three groups dominated by: I – glucose, II – fructose and III – mixed, with a close content of two monosaccharides. This allowed the bands characteristic of α- and β-pyranose forms of glucose and fructose to be identified, as well as the nature of their changes depending on the ratio of both monosaccharides in honey as a result of their crystallisation to be assessed. It is noted that the ratio of monosaccharides determines not only the stability of the liquid crystal structure and crystallisation rate in honey but also their optical, biochemical and nutritional properties, which are important for the preferred use of honey in medical and pharmacopoeial practice, dietetics and cosmetology.

High genetic heterogeneity of Mycobacterium intracellulare isolated from respiratory specimens

Background M. intracellulare is a frequent causative pathogen of nontuberculous mycobacteria infection that causes infections in the respiratory tract, whose incidence is increasing in many countries. This study aimed at determining the VNTR-based genetic diversity of a collection of 39 M. intracellulare human strains isolated from respiratory specimens over the last 5 years. Results The VNTR analysis showed that M. intracellulare strains displayed a high genetic diversity, indicating that the M. intracellulare genotypes are quite heterogeneous in our geographical area. Moreover, a comparison with VNTR profiles of strains from other countries confirmed that genotypes of clinical strains of M. intracellulare are not related to geographical origin. Conclusions VNTR typing has proved to be a highly discriminatory method for better understanding the molecular epidemiology of M. intracellulare.