Transition of survival strategies under global climate shifts in the grape family.

Faced with environmental changes, plants may either move to track their ancestral niches or evolve to adapt to new niches. Vitaceae, the grape family, has evolved diverse adaptive traits facilitating a global expansion in wide-ranging habitats, making it ideal for investigating transition between move and evolve strategies and exploring the underlying mechanisms. Here we inferred the patterns of biogeographic diversification and trait evolution in Vitaceae based on a robust phylogeny with dense sampling including 495 species (~52% of Vitaceae species). Vitaceae probably originated from Asia-the diversity centre of extant genera and the major source of dispersals. Boundaries of the Eocene, Oligocene and Miocene were identified as turning points in shifting strategies. A significant decrease in move strategy was identified during the Oligocene, followed by increases in move and evolve. After the Miocene, evolve began to dominate, during which increased niche opportunities and key trait innovations played important roles.

Novel N,C,S-TiO2/WO3/rGO Z-scheme heterojunction with enhanced visible-light driven photocatalytic performance.

Novel N,C,S-TiO2/WO3/rGO Z scheme photocatalyst was successfully synthesized from graphite, TIOT, and ammonium metatungstate precursors. Material characteristics such as crystal structure, surface morphology, functional groups, specific surface area, elemental composition, band gap energy, and electron-hole recombination were characterized by XRD, TEM, BET, SEM/EDX, FT-IR, UV-VIS, and PL methods. The as-synthesized novel N,C,S-TiO2/WO3/rGO Z-scheme heterojunction photocatalyst exhibited visible light-driven photocatalytic activity (the band gap energy = 2.24 eV), could generate both effective electrons and holes, and presented the lowest electron-hole recombination rate compared to all individual components. Different factors impacting the photocatalytic decomposition of Direct Blue 71 (DB 71) by the N,C,S-TiO2/WO3/rGO system were studied. The results showed that pH of the solution, catalyst load, DB 71 initial concentration, and reaction time affected the DB 71 photocatalytic degradation efficiency. The DB 71 degradation completed after 100 min with a typical efficiency of over 91%, which was much better than other photocatalytic systems. The DB 71 degradation process followed the pseudo-first-order kinetics model with coefficients of determination > 0.95 for all conditions. The photocatalyst was easily regenerated, and exhibited a very good stability, with a photocatalytic degradation efficiency of over 83.0% after 3 cycles.

Historical biogeography of Tetrastigma (Vitaceae): Insights into floristic exchange patterns between Asia and Australia.

Biodiversity exchanges across the Malesian region, linking the distinct biotas of Asia and Australia, have long attracted the curiosity of biologists. Tetrastigma (Vitaceae) has a wide distribution in Asia through the Sunda archipelago to Australia and provides a good case to elucidate floristic exchange between Asia and Australia. Tetrastigma species have fleshy fruits that are consumed by birds, representing a lineage with a predictable dispersal across island chains. We herein estimate the divergence times and reconstruct the biogeographic history of Tetrastigma with intensive taxon sampling (96 of approximately 120 species; >80%) using 10 chloroplast loci. The biogeographic history of Tetrastigma was reconstructed with 4-area and 6-area divisions by delineating the Sunda region into one or three areas of endemism based on a phylogenetic bioregionalization analysis and the geological history of Malesia. The 4-area division shows that Tetrastigma originated in continental Asia and diverged from the recently segregated genus Pseudocayratia in the early Eocene (49.43 Ma). Dispersal from continental Asia might have started in the late Eocene but mainly occurred in the last 10 Myr. Continental Asia is indicated to be the most important source area while Sunda is the biggest sink, with 16 of the 27 dispersal events inferred from continental Asia to Sunda. Only seven dispersal events are inferred arriving in the Sahul plate and one reverse dispersal from Sahul back to Asia. The 6-area division suggests that the Philippines have been an active junction between Asia and Australia. The biogeographic history of Tetrastigma illustrates an asymmetric floristic exchange between Asia and Australia in this genus, which has been facilitated by the formation of terrestrial connections in the late Miocene and the expansion of wet tropical forests across Wallace's Line and beyond.

Evolutionary history of the angiosperm flora of China.

High species diversity may result from recent rapid speciation in a 'cradle' and/or the gradual accumulation and preservation of species over time in a 'museum'. China harbours nearly 10% of angiosperm species worldwide and has long been considered as both a museum, owing to the presence of many species with hypothesized ancient origins, and a cradle, as many lineages have originated as recent topographic changes and climatic shifts-such as the formation of the Qinghai-Tibetan Plateau and the development of the monsoon-provided new habitats that promoted remarkable radiation. However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)). The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04-25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29-18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns. Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.

Robust Phylogeny of Tetrastigma (Vitaceae) Based on Ten Plastid DNA Regions: Implications for Infrageneric Classification and Seed Character Evolution.

Tetrastigma (Miq.) Planch. is one of the most species-rich genera of the economically and agronomically important grape family Vitaceae. It includes ca. 95 species widely distributed in the tropics and subtropics of Asia and Australia. Species of Tetrastigma exhibit great diversity in both vegetative and reproductive characters. Here we inferred a well-supported phylogeny of Tetrastigma based on ten chloroplast DNA regions with an expanded taxon sampling of 72 species and two varieties. Our molecular results support six major clades within Tetrastigma and the relationships among these clades were well-resolved. We also documented seed morphology of 44 species covering the six major clades of the genus. Ancestral states of eight characters (seed shape, seed surface rumination pattern, chalaza length/width ratio, chalaza position, ventral infold position, ventral infold divergence, ventral infold depth in cross section, and endosperm shape) were reconstructed in Mesquite and R with four models. Character optimizations suggest that all character states have evolved multiple times except that the irregular-shaped surface rumination has derived only once in Tetrastigma. We evaluated the taxonomic importance of seed morphology and identified potential morphological evidence to support each major clade. Our comprehensive analyses of Tetrastigma shed insights into the infrageneric classification of this morphologically diverse and ecologically important genus in tropical and subtropical Asia.