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Global climate change poses a severe threat to mountain biodiversity. Phenotypic plasticity and local adaptation are two common strategies for alpine plant to cope with such change. They may facilitate organismal adaptation to contrasting environments, depending on the influences of the environment or genotype or their interacted effects. In this study, we use an endemic alpine plant (Rorippa elata) in the Hengduan mountains (HDM) to unravel its phenotypic basis of adaptation strategy and evaluate the relative contributions of environment and genotype to its phenotype. We transplanted 37 genotypes of R. elata into two common gardens across low and high elevations (2800 vs. 3800 m) during 2021–2022. Nine fitness-related traits were measured, including flowering probability and glucosinolates (GS) content. We estimated the environmental or genotypic contributions to the phenotype and identified the main environmental components. Our results revealed that both environment and genotype-by-environment interactions contributed to the phenotypes of R. elata. Latitudinal heterogeneity was identified as a key factor that explained 24% of the total phenotypic variation. In particular, genotypes of the northern HDM showed significantly higher plasticity in flowering probability than those of the southern HDM. Furthermore, within the southern HDM, GS content indicated local adaptation to herbivory stresses for R. elata genotypes along elevations. In conclusion, our results suggest that R. elata may have adapted to the alpine environment through species-level plasticity or regional-level local adaptation. These processes were shaped by either complex topography or interactions between genotype and mountain environments. Our study provides empirical evidence on the adaptation of alpine plants. [ABSTRACT FROM AUTHOR]

Abstract Background Irritable bowel syndrome (IBS) is a common gastrointestinal functional disease. Adults with IBS may experience abdominal pain, change of bowel habits, and abnormal stool form without organic disease. IBS can seriously affect their work productivity and quality of life, especially diarrhea-predominant irritable bowel syndrome (IBS-D). The Chinese medicine JCM-16021 has been shown to be potentially effective in improving the symptoms of IBS-D based on a small scale clinical trial. Hence, a large scale clinical study is designed to further evaluate the efficacy and safety of the Chinese medicine JCM-16021 for IBS-D with traditional Chinese medicine (TCM) pattern of Liver Stagnation and Spleen Deficiency (LSSD). Methods This study is a multi-center, randomized, double-blind, placebo-controlled clinical trial. 392 eligible participants will be enrolled with 2-week run-in, 8-week treatment and 8-week follow-up. After run-in period, participants will be randomized to receive either the Chinese medicine JCM-16021 or placebo for 8 weeks, and will have post-treatment follow up for another 8 weeks. The primary outcome is the improvement rate on the global assessment of improvement (GAI) at week 10. The secondary outcomes consist of changes of IBS-D symptoms, TCM pattern improvement, IBS-Quality of Life (IBS-QoL), IBS-Symptom Severity Score (IBS-SSS), safety, etc. Results A standard protocol has been developed for the study. The protocol will provided a detailed procedure to conduct a clinical trial and verify if the Chinese medicine JCM-16021 would significantly improve the overall symptoms of IBS-D with LSSD pattern of TCM by relieving abdominal pain, reducing stool frequency, improving the stool consistency and improving quality of life. The consolidated evidence from the study can shed light on the treatment of IBS-D with Chinese medicine. Conclusion The protocol will provide details for investigators about the study following SPIRIT Statement. High-quality evidence on the efficacy and safety of Chinese medicine JCM-16021 for IBS-D will be provided through strict compliance with the protocol. Trial registration: ClinicalTrial.gov identifier: NCT03457324. Registered 8 February 2018, https://clinicaltrials.gov/ct2/show/NCT03457324?term=NCT03457324&draw=2&rank=1

Aim: Long‐distance dispersal (LDD) plays an important role in shaping the distribution of global biodiversity. Polyploidy could favour invasion and thereby facilitate LDD. However, how and to what extent polyploidy interacts with LDD remain unclear. Here, we test the putative role of polyploidy in the global dispersal of a cosmopolitan genus Rorippa. Location: Global. Time Period: Late Miocene to present. Major Taxa Studied: Rorippa Scop., Brassicaceae. Methods: We traced the biogeographical and speciation history for 17 diploids and 41 polyploids of Rorippa using variation from plastid genomes and multiple nuclear loci. The ploidy role in dispersal rate difference was demonstrated using trait‐dependent biogeographical modelling. Results: LDD shaped the amphitropical disjunction of Rorippa, during which polyploids showed higher dispersal rates than those of diploids, with 5.6× increase under the best‐fitted model. Five diploids and 21 polyploids were identified as products of transoceanic speciation events. Polyploidy‐involved LDD was more common in terms of polyploidization following LDD than those preceding LDD. Main Conclusions: We demonstrate that polyploidy would be not only a driver but also a responder of LDD in Rorippa, highlighting a synergistic relationship between them. Our results provide a framework to uncover the biogeographical consequences of polyploidization and the joint roles of polyploidy and LDD in shaping the distribution of biodiversity. [ABSTRACT FROM AUTHOR]

Ulmaceae is a woody family widespread in northern temperate forests. Despite the ecological importance of this family, its phylogeny and biogeographic history are poorly understood. In this study, we reconstruct phylogenetic relationships within the family and infer spatio‐temporal diversification patterns based on chloroplast genome (complete cpDNA) and nuclear ribosomal DNA sequences (nrDNA). The seven Ulmaceae genera are resolved in two main clades (temperate vs. tropical) by both cpDNA and nrDNA sequences. The temperate clade includes four genera, Hemiptelea, Zelkova, Planera, and Ulmus. The relationships among Planera and other genera are controversial because of inconsistent topologies between plastid and nuclear data. The tropical clade includes three genera ((Ampelocera, Phyllostylon), Holoptelea). Molecular dating and diversification analyses show that Ulmaceae originated in the Early Cretaceous (ca. 110–125 Ma) with the main lineages establishing from the Late Cretaceous to the early Eocene. The diversification rate slowed during the middle to the late Paleogene (ca. 23–45 Ma), followed by a rapid diversification of the East Asian temperate group in the Neogene, congruent with a global cooling event. The ancestral state optimization analysis suggests an East Asian origin of the temperate Ulmaceae clade during the Paleocene, which is consistent with the fossil record. Both phylogenomic and fossil evidence support East Asia as a center of origin and diversification for the temperate woody lineages. [ABSTRACT FROM AUTHOR]

The Asian paleotropical flora is characterized by abundance of endemic species, high biodiversity, and complex geological and climatic histories. However, the main driving mechanism underlying such high tropical biodiversity remains unclear. Hence, the present study aimed to investigate the biogeographic origin of the Asian paleotropical flora by tracking the speciation and diversification history of a typical tropical perennial, Typhonium sensu stricto (s.s.) (Araceae), using a time‐calibrated whole‐plastome phylogeny. In particular, we tested whether the Asian paleotropic region is a macroevolutionary source or sink. We observed that Typhonium s.s. originated in Indochina during the early–middle Miocene epoch, ca. 17.24 Ma (95% highest posterior density [HPD]: 12.83 ̶ 21.99 Ma). Most of the in situ diversification within the genus Typhonium s.s. has been underway since 14.73 Ma, with an accelerated lineage diversification at ca. 15−17 Ma, which may have been triggered by the intensification of the Asian monsoon system around the middle Miocene. Furthermore, the underground tuberous stem of Typhonium s.s. might have played an essential role in the adaptation to the seasonality caused by the monsoon in Indochina. Our results also suggested that peripatric speciation may be important in the diversification of T. trilobatum and T. roxburghii. This study provides a framework for studies in biogeography and evolution of the Asian paleotropical flora. [ABSTRACT FROM AUTHOR]

The extinct genus Limnobiophyllum (Araceae) has been considered a tentative link between the Aroideae and Lemnoideae subfamilies of Araceae. General understanding of morphological character evolution among these subfamilies has been limited due to the lack of preserved key structures in fossils such as infructescences. In this study, a new fossil species, Limnobiophyllum pedunculatum Low, Su & Xing sp. nov., is reported based on unusually complete specimens with intact leaves, stolon and attached infructescence and seeds from the late Oligocene of central Tibet, China. It represents the first convincing Limnobiophyllum fossil from the Tibetan Plateau and the first well-documented occurrence from east Asia. Its phylogenetic position was inferred using a matrix of 56 morphological characters and 5226 gene sequences of 41 taxa. Phylogenetic inference based on the matrix suggests that Limnobiophyllum is sister to Cobbania, as well as to the remaining extinct and living genera within the Araceae subfamily Lemnoideae. Reconstruction of vegetative and reproductive character evolution confirms that Limnobiophyllum possessed intermediate characters, especially for infructescences, between the subfamilies Lemnoideae and Aroideae. Within Lemnoideae, both vegetative and reproductive characters show clear reduction and simplification from extinct genera to living lemnoids. These findings shed new light on the evolutionary history of the family Araceae. In addition, the discovery of this species, in association with the surrounding plant megafossil assemblage, suggests a warm, humid lowland environment in the central Tibetan Plateau during the late Oligocene, contradicting previous studies that indicated high elevation of the plateau since the early Palaeogene. However, the extinction of Limnobiophyllum might have been due to both global cooling and orogenesis. [ABSTRACT FROM AUTHOR]