Dwarf bamboo (Fargesia denudata) is a crucial food source for the giant pandas. With its shallow root system and rapid growth, dwarf bamboo is highly sensitive to drought stress and nitrogen deposition, both major concerns of global climate change affecting plant growth and rhizosphere environments. However, few reports address the response mechanisms of the dwarf bamboo rhizosphere environment to these two factors. Therefore, this study investigated the effects of drought stress and nitrogen deposition on the physicochemical properties and microbial community composition of the arrow bamboo rhizosphere soil, using metagenomic sequencing to analyze functional genes involved in carbon and nitrogen cycles. Both drought stress and nitrogen deposition significantly altered the soil nutrient content, but their combination had no significant impact on these indicators. Nitrogen deposition increased the relative abundance of the microbial functional gene nrfA, while decreasing the abundances of nirK, nosZ, norB, and nifH. Drought stress inhibited the functional genes of key microbial enzymes involved in starch and sucrose metabolism, but promoted those involved in galactose metabolism, inositol phosphate metabolism, and hemicellulose degradation. NO₃⁻-N showed the highest correlation with N-cycling functional genes (p < 0.01). Total C and total N had the greatest impact on the relative abundance of key enzyme functional genes involved in carbon degradation. This research provides theoretical and technical references for the sustainable management and conservation of dwarf bamboo forests in giant panda habitats under global climate change.

The genus Aletris L. (Nartheciaceae) encompasses approximately 21–24 species distributed in East Asia and North America, yet taxonomic ambiguity persists due to overlapping morphological traits among closely related species. During fieldwork in southeastern Xizang, China, a morphologically distinct candidate species, Aletris medogensis , was discovered. To validate its taxonomic status and explore evolutionary relationships within East Asian Aletris , we integrated detailed morphological observation with comparative chloroplast phylogenomics. The newly proposed species is characterized by creeping stolons, narrow leaves, and glandular‐pubescent inflorescences. Comparative analysis of 14 East Asian Aletris complete chloroplast genomes revealed a conserved quadripartite structure with species‐specific variations, including pseudogenization of ycf1 , loss of rrn4.5 , and shifts in IR boundaries. Phylogenomic analyses strongly supported A. medogensis as a distinct species closely related to A. alpestris . We identified 18 hypervariable regions as potential molecular markers and detected signals of positive selection in genes ccsA , cemA , and rps12 , suggesting adaptive evolution. This study confirms the recognition of A. medogensis as a new species endemic to the eastern Himalayas and demonstrates the utility of chloroplast genomics in resolving taxonomic complexity and understanding evolutionary mechanisms in Aletris .

We document and illustrate Primula xideensis, a new species collected from Xide County, Sichuan Province, China. Morphologically, it resembles P. stenocalyx, P. farinosa s.l., and P. pulchella, but differs by its roots densely covered with multicellular hairs; elliptic to obovate leaves with non-revolute, irregularly and deeply dentate margins, both surfaces efarinose, shortly hairy, and scabrous; tubular calyx parted to the middle; corolla mouth densely white-farinose; stamens positioned at mid-corolla tube in pin flowers and near the throat in thrum flowers; styles reciprocally placed; and an oblong capsule shorter than the persistent calyx. To clarify its phylogenetic placement, we constructed phylogenetic trees using two datasets: 63 complete chloroplast genome sequences and 75 nuclear ribosomal DNA internal transcribed spacer (nrITS) sequences. Both trees showed similar topologies, consistently placing the new species within a monophyletic group of Sect. Aleuritia, supporting its assignment to this section. For a deeper comparison between the new species and other members of Sect. Aleuritia, we incorporated chloroplast genomes of seven additional species from this section. The results revealed highly conserved chloroplast genomes among all eight species, with only minor differences between the new species and the others. Primula xideensis is currently known only from its type locality. Based on IUCN Red List criteria, its conservation status is assessed as Data Deficient (DD).

Campylotropis guizhouensis, a new species from Guizhou Province, Southwest China, is described and illustrated. It is morphologically similar to C. sulcata and molecularly closely related to C. trigonoclada, but can be distinguished from both species by its terete appressed-pubescent branchlets with minute angles and obscure sulci, linear-lanceolate stipules, subdensely appressed-pubescent leaf abaxial surfaces, axillary and terminal single raceme, smaller lanceolate bracts, and obliquely ovate to near-semicircular legumes. Molecular phylogenetic analysis also indicates that the new species forms an independent lineage, clearly separate from the morphologically similar C. sulcata. Additional information of this new species, including its phenology, distribution, habitat and etymology, is also provided.

The genus Sorbus sensu lato (Maleae, Rosaceae) represents one of the most taxonomically complex groups in Rosaceae due to extensive hybridization, polyploi