Medicinal plants have long been used to treat various diseases in both indigenous and non-indigenous populations of Mindanao, Philippines. Here, we extracted data from ethnobotanical studies to compile a comprehensive list of these medicinal plants and identify how and for what purpose they are most commonly used. We identified 530 verified medicinal plant species across 372 genera in 118 families. The two most frequently cited species were Euphorbia hirta and Psidium guajava. The most represented family was Fabaceae and the most represented genus was Ficus. A total of 28 medicinal plant species are designated as threatened at the national or global level; of these, 11 are endemic to the Philippines. Medicinal plant preparations most commonly use leaves for oral administration to treat various diseases such as digestive issues, including diarrhea. This study underscores the need for further ethnobotanical investigations, particularly in areas lacking records. It also emphasizes the need for conservation of threatened and endemic medicinal plants to ensure sustainable utilization of this valuable resource.

Mountain biodiversity is of great importance to biogeography and ecology. However, it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diversity. In this study, we determined which of six common hypotheses (e.g., climate hypotheses, habitat heterogeneity hypothesis and island biogeography theory) best explain global patterns of species diversity in Rhododendron. We found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory (i.e., mountain area) and habitat heterogeneity (i.e., elevation range). When we examined other relationships important to island biogeography theory, we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity, whereas the ‘mountains-to-mainland’ distance was negatively correlated with Rhododendron diversity and shared species. Our findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity, and mountains can be regarded as islands which supported island biogeography theory.

Understanding genome-wide diversity, inbreeding, and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience. However, these effects are rarely studied in limestone karst plants. Here, we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex (B. liuyanii, B. longgangensis, B. masoniana and B. variegata) and investigated genomic divergence and genetic load for these four species. Our analyses revealed four distinct clusters corresponding to each species within the complex. Notably, there was only limited admixture between B. liuyanii and B. longgangensis occurring in overlapping geographic regions. All species experienced historical bottlenecks during the Pleistocene, which were likely caused by glacial climate fluctuations. We detected an asymmetric historical gene flow between group pairs within this timeframe, highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation. We found that isolated populations of B. masoniana have limited gene flow, the smallest recent population size, the highest inbreeding coefficients, and the greatest accumulation of recessive deleterious mutations. These findings underscore the urgency to prioritize conservation efforts for these isolated population. This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level, shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding. Moreover, our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere. Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations. One of these relict lineages is Dipteronia, an oligotypic tree genus with a fossil record extending to the Paleocene. Here, we investigated the genetic variability, demographic dynamics and diversification patterns of the two currently recognized Dipteronia species (Dipteronia sinensis and D. dyeriana). Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions, two single copy nuclear genes and 15 simple sequence repeat loci. The genetic study was combined with niche comparison analyses on the environmental space, ecological niche modeling, and landscape connectivity analysis. We found that the two Dipteronia species have highly diverged both in genetic and ecological terms. Despite the incipient speciation processes that can be observed in D. sinensis, the occurrence of long-term stable refugia and, particularly, a dispersal corridor along Daba Shan-west Qinling, likely ensured its genetic and ecological integrity to date. Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic, but also provide insight into how Arcto-Tertiary relict plants in East Asia survived, evolved, and diversified.

The common walnut (Juglans regia) is one of the most economically important nut trees cultivated worldwide. Despite its importance, no comprehensive evaluation of walnut tree population genetics has been undertaken across the range where it originated, Central Asia. In this study, we investigated the genetic diversity and population structure of 1082 individuals from 46 populations across Central Asia. We found moderate genetic diversity of J. regia across Central Asia, with 46 populations clustered into three groups with a weak relationship between genetic and geographic distance. Our findings reveal that the western Himalaya might be the core region of common walnut genetic diversity in Central Asia and that, except for two populations in Gongliu Wild Walnut Valley, humans might have introduced walnut populations to Xinjiang, China. The observed distribution of the genetic landscape has probably been affected by historical climate fluctuation, breeding system, and prolonged anthropogenic activity. We propose the conservation of the core genetic diversity resources in the western Himalaya and pay special attention to populations from Gongliu in Xinjiang. These findings enhance our understanding of the genetic variation throughout the distribution range of J. regia in Central Asia, which will provide a key prerequisite for evidence-based conservation and management.

Tropical regions have provided new insights into how ecological communities are assembled. In dry coastal communities, water stress has been hypothesized to determine plant assembly structure by favoring preadapted lineages from neighboring ecosystems, consistent with functional clustering. However, it is unclear whether this hypothesis is sufficient to explain how coastal communities in tropical ecosystems are assembled. Here, we test whether water stress or other factors drive community assembly in woody plant communities across the coastal zone of Brazil, a tropical ecosystem. We characterized functional and phylogenetic structures of these communities and determined the underlying environmental factors (e.g., water stress, historical climate stability, edaphic constraints, and habitat heterogeneity) that drive their community assembly. Assemblages of coastal woody species show geographically varied patterns, including stochastic arrangements, clustering, and overdispersion of species relative to their traits and phylogenetic relatedness. Topographic complexity, water vapor pressure, and soil nutrient availability best explained the gradient in the functional structure. Water deficit, water vapor pressure, and soil organic carbon were the best predictors of variation in phylogenetic structure. Our results support the water-stress conservatism hypothesis on functional and phylogenetic structure, as well as the effect of habitat heterogeneity on functional structure and edaphic constraints on functional and phylogenetic structure. These effects are associated with increased phenotypic and phylogenetic divergence of woody plant assemblages, which is likely mediated by abiotic filtering and niche opportunities, suggesting a complex pattern of ecological assembly.

Leaf economics spectrum (LES) describes the fundamental trade-offs between leaf structural, chemical, and physiological investments. Generally, structurally robust thick leaves with high leaf dry mass per unit area (LMA) exhibit lower photosynthetic capacity per dry mass (A_mass). Paradoxically, “soft and thin-leaved” mosses and spikemosses have very low A_mass, but due to minute-size foliage elements, their LMA and its components, leaf thickness (LT) and density (LD), have not been systematically estimated. Here, we characterized LES and associated traits in cryptogams in unprecedented details, covering five evolutionarily different lineages. We found that mosses and spikemosses had the lowest LMA and LT values ever measured for terrestrial plants. Across a broad range of species from different lineages, A_mass and LD were negatively correlated. In contrast, A_mass was only related to LMA when LMA was greater than 14 g cm^-2. In fact, low A_mass reflected high LD and cell wall thickness in the studied cryptogams. We conclude that evolutionarily old plant lineages attained poorly differentiated, ultrathin mesophyll by increasing LD. Across plant lineages, LD, not LMA, is the trait that represents the trade-off between leaf robustness and physiology in the LES.

Macrophyte habitats exhibit remarkable heterogeneity, encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic stressors. Environmental factors are thought to be important drivers shaping the genetic and epigenetic variation of aquatic plants. However, the links among genetic diversity, epigenetic variation, and environmental variables remain largely unclear, especially for clonal aquatic plants. Here, we performed population genetic and epigenetic analyses in conjunction with habitat discrimination to elucidate the environmental factors driving intraspecies genetic and epigenetic variation in hornwort (Ceratophyllum demersum) in a subtropical lake. Environmental factors were highly correlated with the genetic and epigenetic variation of C. demersum, with temperature being a key driver of the genetic variation. Lower temperature was detected to be correlated with greater genetic and epigenetic variation. Genetic and epigenetic variation were positively driven by water temperature, but were negatively affected by ambient air temperature. These findings indicate that the genetic and epigenetic variation of this clonal aquatic herb is not related to the geographic feature but is instead driven by environmental conditions, and demonstrate the effects of temperature on local genetic and epigenetic variation in aquatic systems.

Alien plant invasion success can be inhibited by two key biotic factors: native herbivores and plant diversity. However, few studies have experimentally tested whether these factors interact to synergistically resist invasion success, especially factoring in changing global environments (e.g. nutrient enrichment). Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient conditions. For this purpose, we exposed alien plant species in pot-mesocosms to different levels of native plant diversity (4 vs. 8 species), native generalist herbivores, and high and low soil nutrient levels. We found that generalist herbivores preferred alien plants to native plants, inhibiting invasion success in a native community. This inhibition was amplified by highly diverse native communities. Further, the amplified effect between herbivory and native plant diversity was independent of nutrient conditions. Our results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory tolerance. The synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant species. Our results shed light on the effective control of plant invasions using multi-trophic means, even in the face of future global changes.

Relict subtropical coniferous forests in China face severe fragmentation, resulting in declining populations, and some are under significant threat from invasive alien species. Despite the crucial importance of understanding forest dynamics, knowledge gaps persist, particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana. In this study, we investigated the impact of invasive plants on the regeneration of forests dominated by K. evelyniana, a subtropical relict species in southwestern China. For this purpose, we characterized forest dynamics of 160 forest plots featuring K. evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K. evelyniana. We identified four distinct forest types in which K. evelyniana was dominant. We found that radial growth of K. evelyniana trees is faster in younger age-classes today than it was for older trees at the same age. The population structure of K. evelyniana in each forest type exhibited a multimodal age-class distribution. However, three forest types lacked established saplings younger than 10 years old, a situation attributed to the dense coverage of the invasive alien Ageratina adenophora. This invasive species resulted in a reduction of understory species diversity. Additionally, our analysis uncovered a significant negative correlation in phylogenetic relatedness (net relatedness index) between native and invasive alien plant species in eastern Yunnan. This suggests closely related invasive species face heightened competition, hindering successful invasion. Taken together, our findings indicate that successful establishment and habitat restoration of K. evelyniana seedling/saplings require effective measures to control invasive plants.

Reproductive strategies of sexually dimorphic plants vary in response to the environment. Here, we ask whether the sexual systems of Fagopyrum species (i.e., selfing homostylous and out-crossing distylous) represent distinct adaptive strategies to increase reproductive success in changing alpine environments. To answer this question, we determined how spatial and temporal factors (e.g., elevation and peak flowering time) affect reproductive success (i.e., stigmatic pollen load) in nine wild Fagopyrum species (seven distylous and two homostylous) among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains, southwestern China. We also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility, self-compatibility and pollen limitation in four Fagopyrum species (two distylous and two homostylous). We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads; late-flowering individuals had smaller flowers and lower pollen deposition. Stigmatic pollen deposition was more variable in distylous species than in homostylous species. Although seed set was not pollen-limited in all species, we found that fruit set was much lower in distylous species, which rely on frequent pollinator visits, than in homostylous species capable of autonomous self-pollination. Our findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

We used 11 years of census data from 450 seedling quadrats established in a 20-ha forest dynamics plot to study seedling dynamics in tree species of a tropical seasonal rainforest in Xishuangbanna, southwestern China. We found that overall seedling recruitment rate and relative growth rate were higher in the rainy season than in the dry season. Both the recruitment rate of seedlings from canopy tree species (two species) and the relative growth rate of seedlings from understory species (nine species) were higher in the rainy season than in the dry season. However, in the rainy season, the recruitment rate of seedlings was higher for canopy tree species than for understory tree species. In addition, relative growth rate of seedlings was higher in the canopy species than in understory seedlings in the dry season. We also observed that, in both rainy and dry seasons, mortality rate of seedlings was higher for canopy species than for understory species. Overall, canopy tree species appear to have evolved a flexible strategy to adapt to the seasonal changes of a monsoon climate. In contrast, understory tree species seem to have adopted a conservative strategy. Specifically, these species mainly release seedlings in the rainy season and maintain relatively stable populations with a lower mortality rate and recruitment rate in both dry and rainy seasons. Our study suggests that canopy and understory seedling populations growing in forest understory may respond to future climate change scenarios with distinct regeneration strategies.