This article studies the morphological parameters of vegetative and generative organs of different age groups of Crataegus ambigua from four populations in Western Karatau (Mangistau region, Kazakhstan). In this study, we examined four populations: Sultan Epe, Karakozaiym, Emdikorgan, and Samal, all located in various gorges of Western Karatau. Several phylogenetic inference methods were applied, using six genetic markers to reconstruct the evolutionary relationships between these populations: atpF–atpH, internal transcribed spacer (ITS), matK, psbK–psbI, rbcL, and trnH–psbA. We also used a statistical analysis of plants’ vegetative and generative organs for three age groups (virgin, young, and adult generative). According to the age structure, Samal has a high concentration of young generative plants (42.3%) and adult generative plants (30.9%). Morphological analysis showed the significance of the parameters of the generative organs and separated the Samal population into a separate group according to the primary principal component analysis (PCoA) coordinates. The results of the floristic analysis showed that the Samal populations have a high concentration of species diversity. Comparative dendrograms using UPGMA (unweighted pair group method with arithmetic mean) showed that information gleaned from genetic markers and the psbK–psbI region can be used to determine the difference between the fourth Samal population and the other three.

This study investigates the anatomical adaptations and ecological plasticity of C. ambiguus in extreme environmental conditions by analyzing the structural characteristics of its leaves and annual shoots collected from 12 populations in the arid regions of Mangystau, including Western Karatau, Northern Aktau, and the Tyubkaragan Peninsula. Microscopic and statistical analyses revealed significant variability in key anatomical traits, including epidermal thickness, collenchyma, primary cortex, and vascular bundle area, highlighting the species’ adaptive responses to drought, high solar radiation, and limited water availability. The epidermal thickness ranged from 14.85 µm (Pop_12 Botakan) to 22.51 µm (Pop_6 Samal), demonstrating xeromorphic adaptations for reducing transpiration. At the same time, the vascular bundle area varied from 286.06 × 10⁻³ mm² (Pop_3 Emdikorgan) to 528.51 × 10⁻³ mm² (Samal), indicating differences in water transport efficiency across populations. Despite substantial anatomical variation, the low coefficients of variation (0.31%–6.31%) suggested structural stability, reinforcing C. ambigua’s ability to maintain functional integrity under environmental stress. Canonical Correlation Analysis (CCA) confirmed that environmental factors such as soil type, elevation, and water availability significantly influenced anatomical traits. Floristic analysis revealed distinct patterns of species richness, with the highest diversity recorded in Pop_4 and Pop_7, while Pop_12 and Pop_9 exhibited lower diversity, indicating potential vulnerability. Furthermore, the identified anatomical traits could serve as key markers for selecting drought-resistant genotypes in afforestation and restoration programs. This study also highlighted the need for the long-term monitoring of C. ambigua populations to assess the impact of climate change on structural adaptations. These findings offer a framework for integrating ecological and genetic studies to refine conservation strategies for xerophytic species.

Alhagi pseudalhagi, which grows in the arid zone of the Atyrau region, and an assessment of the current state of its raw material reserves were studied. Botanical characteristics, ontogenetic spectra, morphological indicators, productivity, areas of thickets, and reserves of raw materials of above-ground organs were assessed. The structural parameters of these populations in the Zhangyr and Coneu Rivers valleys, in the vicinity of Imankara Mountain, and on the Taisoigan sands were studied. It was established that the species composition of the populations includes 63 species from 54 genera and 30 families. The most common species include 49 species, which, according to their occurrence in populations of A. pseudalhagi, are distributed in the following classes: 17 species—class II (0–20%); 7 species—class III (41–60%); and 2 species—classes IV (61–80%) and V (81–100%). The maximum similarity in species composition was noted between populations in the Zhangyr and Coneu Rivers valleys. The highest morphometric indicators were observed among the population of the Coneu river valley, and the lowest are located on the Taisoigan sands. Analysis of the age spectra made it possible to determine that the populations in the Zhangyr and Coneu River valleys are characterized as young and those in the area of Imankara Mountain and on the Taisoigan sands as stable and middle-aged.

This article studies the morphological parameters of vegetative and generative organs of different age groups of Crataegus ambigua from four populations in Western Karatau (Mangistau region, Kazakhstan). The study examined four populations Pop 1 Sultan Epe, Pop 2 Karakozaiym, Pop 3 Emdikorgan, and Pop 4 Samal located in various gorges of western Karatau. Some phylogenetic inference methods were applied using six genetic markers atpF-atpH, ITS, matK, psbK-psbI, rbcL, and trnH-psbA. We also used a statistical analysis of the vegetative and generative organs of plants for three age groups of plants (virgin, young generative, and adult generative). According to the age structure, Samal populations have a high concentration of young generative plants - 42.3% and adult generative plants - 30.9%. Morphological analysis showed the significance of the parameters of the generative organs and separated the Samal population into a separate group according to the main PCoA coordinates. The results of the floristic analysis showed that the populations in the Samal have a high concentration of species diversity. The comparative dendrogram of UPGMA shows the informativeness of the use of genetic markers and the psbK-psbI region can be used to judge the difference between the fourth Samal population and the other three.