Hippophae rhamnoides subsp. sinensis is extensively found in China, where the annual precipitation ranges from 400 to 800 mm. It is the most dominant species in natural sea buckthorn forests and the primary cultivar for artificial ecological plantations. Additionally, it exhibits significant nutritional and medicinal value, making it a renowned eco-economic tree species. Despite extensive research into its ecological functions and health benefits, the mitochondrial genome of this widespread species has not yet been published, and knowledge of the mitochondrial genome is crucial for understanding plant environmental adaptation, evolution, and maternal inheritance. Therefore, the complete mitochondrial genome was successfully assembled by aligning third-generation sequencing data to the reference genome sequence using the Illumina NovaSeq 6000 platform and Nanopore Prometh ION technologies. Additionally, the gene structure, composition, repeat sequences, codon usage bias, homologous fragments, and phylogeny-related indicators were also analyzed. The results showed that the length of the mitochondrial genome is 454,489 bp, containing 30 tRNA genes, three rRNA genes, 40 PCGs, and two pseudogenes. A total of 411 C-to-U RNA editing sites were identified in 33 protein-coding genes (PCGs), with higher frequencies observed in ccmFn, ccmB, nad5, ccmC, nad2, and nad7 genes. Moreover, 31 chloroplast-derived fragments were detected, accounting for 11.86% of the mitochondrial genome length. The ccmB, nad4L, and nad7 genes related to energy metabolism exhibited positive selection pressure. The mitochondrial genome sequence similarity between H. rhamnoides subsp. sinensis and H. tibetana or H. salicifolia was 99.34% and 99.40%, respectively. Fifteen shared gene clusters were identified between H. rhamnoides subsp. sinensis and H. tibetana. Phylogenetically, the Rosales order showed close relationships with Fagales, Fabales, Malpighiales, and Celastrales. These findings provide fundamental data for exploring the widespread distribution of H. rhamnoides subsp. sinensis and offer theoretical support for understanding the evolutionary mechanisms within the Hippophae genus and the selection of molecular breeding targets.

Ecology and adaptive differentiation of Epimedium are central to understanding both its taxonomic complexity and medicinal value. In this study, we integrate transcriptomic and plastid data from four natural populations of E. brevicornu (HZ, QLH, TS, WD) to reconstruct their phylogenetic relationships, estimate divergence times, and identify candidate genes associated with local adaptation. Nuclear gene-based phylogenies provide higher resolution and greater topological consistency than plastid data, underscoring the utility of nuclear data in lineages affected by hybridization and incomplete lineage sorting. Molecular dating indicated that major intraspecific divergence occurred during the mid-Quaternary (0.61–0.45 Ma), coinciding with climatic oscillations and montane isolation. Population structure showed strong correlations with temperature and precipitation gradients, suggesting environmentally driven selection. Signatures of positive selection and accelerated evolutionary rates revealed population-specific enrichment of genes involved in stress response, protein modification, signaling, and carbohydrate metabolism—key pathways linked to high-elevation adaptation. Protein–protein interaction networks further indicated a two-tier adaptation mechanism: ancestral network rewiring combined with population co-evolution of interacting genes. Together, these findings advance our understanding of alpine plant adaptation and provide candidate genes for further functional and breeding studies in Epimedium.

The synergistic effects of climate change and human activities have profoundly influenced the spatiotemporal dynamics of vegetation in arid and semi-arid regions. In this study, MODIS NDVI data and an integrated methodological approach, including trend analysis, partial correlation, residual regression, and geographical detector modeling, were used to analyze the variations in NDVI in Gansu Province from 2000 to 2022. The results showed the following: (1) The growing-season NDVI in Gansu Province exhibited a significant increasing trend overall (0.0029 per year, p < 0.05). (2) Both the NDVI values and their increasing rates presented a spatial pattern of “higher in the southeast and lower in the northwest”; although low vegetation coverage dominated the entire province, 49.47% of the area showed an extremely significant increasing trend in NDVI (p < 0.01). (3) In the future, the area ratio of regions with improved NDVI to those with degraded NDVI in Gansu Province will be approximately 45.5%:54.5%. (4) The contribution rate of human activities to the spatiotemporal variations in NDVI was higher than that of climate change; however, the synergistic effect of the two factors was greater than their individual effects. (5) Precipitation and solar radiation were the two primary climatic factors affecting NDVI variations in Gansu Province, while human activities played a regulatory role in mediating climate–vegetation interactions. Therefore, we suggest implementing more proactive ecological management and restoration measures to mitigate the impacts of future climate change, particularly in regions where NDVI may degrade in the future.

Epimedium brevicornu is an important medicinal plant in China, whose main bioactive components are flavonoid glycosides. UDP-glycosyltransferases (UGTs) play key roles in flavonoid glycosylation and metabolic diversification. In this study, transcriptome data from four representative production regions in Gansu Province were used to systematically identify and analyze the UGT gene family in E. brevicornu. A total of 359 UGT members were identified, and 168 homologous genes with clear expression evidence were obtained from four geographical populations. Molecular evolutionary analysis showed that most UGT genes were under purifying selection, whereas UGT2, UGT52, UGT57, UGT241, UGT269, and UGT271 exhibited significant signals of positive selection in specific lineages (p < 0.05). Protein interaction analysis indicated that many UGT proteins were closely associated with key enzymes involved in flavonoid biosynthesis, including CHS (TT4), CHI (TT5), F3H, FLS, and DFR, suggesting their potential involvement in flavonoid metabolism. Promoter analysis further revealed a high enrichment of ERF (11,169 occurrences) and MYB (7673 occurrences) transcription factor binding sites in the upstream regions of UGT genes. In addition, UGT57 and UGT241 showed significantly higher expression levels in the QLH population. Molecular docking analysis indicated relatively strong binding affinities with quercetin, with binding energies of −7.23 kcal/mol and −4.62 kcal/mol, respectively. These results suggest that the sequence variation and differential expression of UGT genes may be associated with flavonoid glycosylation and ecological adaptation in Epimedium. This study provides a basis for understanding the evolutionary characteristics and expression patterns of the UGT gene family and offers candidate genes for future studies on flavonoid metabolism.

This study conducted a genome-wide identification and functional analysis of the glutathione S-transferase (GST) gene family in the xerophytic desert shrub Reaumuria soongorica. A total of 67 GST genes were identified, classified into seven subfamilies, including Phi and Tau, with family expansion primarily attributed to small-scale duplication events. The findings revealed that ResoGST52, a member of the Tau subfamily, serves as a core gene in drought response, exhibiting significant upregulation of 2.40-fold in leaves and 9.01-fold in roots under drought stress. Mechanistic investigations indicated that the expression of ResoGST52 is likely directly regulated by the transcription factor ResoDof17, with specific hydrogen bonding interactions identified between the two. Co-expression network analysis further demonstrated that ResoGST52 cooperates with key pathways such as plant hormone signaling, MAPK cascades, and glutathione metabolism to collectively respond to drought stress. Notably, evolutionary analysis revealed that ResoGST52 has undergone positive selection, with three positively selected sites identified. Among these, the p.Ala115Ser mutation increases the volume of the protein’s active site pocket, while the remaining mutations enhance surface hydrophobicity, thereby improving protein stability and catalytic efficiency under extreme drought conditions. In summary, this study not only systematically identifies the GST gene family in R. soongorica but also elucidates the central role of ResoGST52 in drought adaptation through multiple layers—from transcriptional regulation and co-expression networks to protein structural adaptive evolution—providing valuable candidate genes and theoretical insights for genetic improvement of drought tolerance in crops.

As a critical alpine transition zone linking the Qinghai–Tibet Plateau and the Loess Plateau, Gannan Prefecture acts as an important water conservation area in the upper Yellow River basin of China. Based on GLDAS-2.1 surface soil moisture (SSM) datasets spanning 2000–2022 and interpretable machine learning tools (SHAP and ALE), this paper analyzes the spatiotemporal evolution, future trend sustainability, and nonlinear statistical associations between environmental predictors and SSM. The main results were as follows: (1) SSM exhibited a significant upward trend with an annual growth rate of 0.18 kg·m⁻²·a⁻¹ (p < 0.001), and an abrupt turning point occurred in 2017. The spatial pattern of high SSM in the southeast and low SSM in the northwest remained relatively stable, with the centroid migration distance being less than 1.81 km; most regions presented statistically significant moistening trends (p < 0.05). (2) Natural environmental predictors jointly carried 95.79% of the total statistical explanatory weight for modeled SSM variability. Precipitation possessed the highest explanatory proportion (37.93%), followed by temperature (27.30%), potential evapotranspiration (ET_p, 12.26%), elevation (10.44%), and fractional vegetation cover (FVC, 7.77%). One-dimensional ALE curves identified sample-limited statistical breakpoints: SSM gradually plateaued when precipitation reached 650–700 mm, while modeled SSM decreased substantially once ET_p exceeded 800 mm·a⁻¹. Two-dimensional ALE further characterized combined statistical correlations among precipitation, temperature, and ET_p. Model outputs also indicated that FVC above 0.45 corresponded to enhanced soil water retention within the observed sample range, which only reflects statistical patterns captured in this dataset rather than universal regulatory standards. This study offers quantitative statistical understanding of SSM variations across alpine transition zones.