Nitrogen and phosphorous are critical determinants of plant growth and productivity, and both plant growth and root morphology are important parameters for evaluating the effects of supplied nutrients. Previous work has shown that the growth of Acer mono seedlings is retarded under nursery conditions; we applied different levels of N (0, 5, 10, and 15 g plant-1) and P (0, 4, 6 and 8 g plant-1) fertilizer to investigate the effects of fertilization on the growth and root morphology of four-year-old seedlings in the field. Our results indicated that both N and P application significantly affected plant height, root collar diameter, chlorophyll content, and root morphology. Among the nutrient levels, 10 g N and 8 g P were found to yield maximum growth, and the maximum values of plant height, root collar diameter, chlorophyll content, and root morphology were obtained when 10 g N and 8 g P were used together. Therefore, the present study demonstrates that optimum levels of N and P can be used to improve seedling health and growth during the nursery period.

The modern genetic structure in this species can be explained by extensive gene flow, an absence of mountains acting as barriers, and the presence of a wide refuge across NEC rather than multiple small refugia. Intra-population genetic variation along latitudes is probably associated with the systematically northward shifts of forest biomes in eastern China during the mid-Holocene. To determine important genetic patterns and identify resources for conservation, however, it will be necessary to examine differentially inherited genetic markers exposed to selection pressures (e.g. chloroplast DNA) and to investigate different generations.

Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE), whereas it has a scattered and patchy distribution in South China (SC). In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM). Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species’ evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST = 0.073; G′ST = 0.278) among all populations, but significantly higher in the SC group than the NE group, mirroring the species’ more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

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Purpose of Review This review provides perspectives and insights of forest researchers from four continents representing a range of geo-regions, with examples from diverse and dynamic use of forest products that are undervalued and often misrepresented. A comprehensive discussion of the subject provides special attention to property, tenancy, public goods and access rights to non-wood forest products (NWFP), seen as forest ecosystem services in a framework for forest management decisions. The overall purpose is to provide a logical argument for transitioning to sustainable management of forests for timber and NWFP. Recent Findings Multifunctional ecosystem-based approaches are transforming our understanding of forests. The prevailing economic relevance of NWFP for trade and sustenance requires their operative integration into forest management. Integration of NWFP will shift a traditional timber-oriented management paradigm towards an inclusive ecosystem forest management approach. We show that the impact of NWFP resources on livelihoods provides multiple benefits to all sectors of global society. Policy and property rights affect the availability and sustainability of the resource, while regulations, restrictions and prohibitions target the sustainable harvest of NWFP under growing demand. Official reporting of production volumes of NWFP is sparse, erratic or inaccurate due to a complex system that is opaque and with inadequately understood value chains, yet research is underway to better understand all NWFP sectors. Summary A shift from command-and-control forest management to broader governance schemes is observed, yet despite a growing awareness of their importance, NWFP and their potential for a bio-based economy require more research. A conceptual framework for transitioning to sustainable co-production management of timber and NWFP is presented. Such a transition is needed to ensure long-term forest security, health and resilience.

Landscape genetics increasingly focuses on the way in which landscape features cause the fragmentation of lineages of terrestrial organisms. However, landscape features can also provide functional connectivity or corridors, enhancing the dispersal of plant populations, particularly the case in riparian habitat. Unfortunately, recent research in tree genetics has paid little attention to this role. To examine the possible effects of landscape connectivity on the current population genetic distribution of Fraxinus mandshurica and to provide insights into conserving the local genetic diversity for this endangered tree species, we used nine nuclear microsatellite loci to examine the spatial genetic structure of F. mandshurica at multiple-scales over a riparian-mountain landscape in Northeast China. F-statistics indicated that the magnitude of among-population genetic differentiation was significantly higher between the riparian and mountain habitats than within the riparian habitat. Spatial analysis of molecular variance and principal coordinate analysis consistently revealed that this species exhibited a clear landscape genetic structure between the riparian and mountain habitats, despite no significant isolation by distance pattern being identified by the Mantel test. Spatial autocorrelation analysis further demonstrated significant, positive fine-scale spatial genetic structure among individuals over short distances (\80 m) in each mountain population. Conversely, no spatial genetic structures were identified within and among the riparian populations. Overall, the results suggest that seed dispersal is very low among mountain populations; however seed transport is probably enhanced by a secondary phase of hydrochory (water-dispersal) among riparian populations during flooding. Despite this, there was no significant accumulation of genetic diversity in downstream populations along the main channel. This result suggests that hydrochory is not sufficient to produce a clear unidirectional gene flow along the water course, although it may impede the development of spatial genetic structuring within and among riparian populations.

Araliaceae species produce various classes of triterpene and triterpenoid saponins, such as the oleanane-type triterpenoids in Aralia species and dammarane-type saponins in Panax, valued for their medicinal properties. The lack of genome sequences of Panax relatives has hindered mechanistic insight into the divergence of triterpene saponins in Araliaceae. Here, we report a chromosome-level genome of Aralia elata with a total length of 1.05 Gb. The loss of 12 exons in the dammarenediol synthase (DDS)-encoding gene in A. elata after divergence from Panax might have caused the lack of dammarane-type saponin production, and a complementation assay shows that overexpression of the PgDDS gene from Panax ginseng in callus of A. elata recovers the accumulation of dammarane-type saponins. Tandem duplication events of triterpene biosynthetic genes are common in the A. elata genome, especially for AeCYP72As, AeCSLMs, and AeUGT73s, which function as tailoring enzymes of oleanane-type saponins and aralosides. More than 13 aralosides are de novo synthesized in Saccharomyces cerevisiae by overexpression of these genes in combination. This study sheds light on the diversity of saponins biosynthetic pathway in Araliaceae and will facilitate heterologous bioproduction of aralosides.

Background: Oxaliplatin (OXA) resistance is a main obstacle to the chemotherapy of colorectal cancer (CRC). Epithelial-mesenchymal transition (EMT), which is mainly regulated by TGF-β/Smad signaling pathway, has gradually been recognized as an important mechanism for tumor chemoresistance. Studies have shown that curcumin regulated EMT processes in many human cancers. However, whether curcumin could regulate OXA resistance in CRC through modulating TGF-β/Smad signaling-mediated EMT remains unclear. Methods: In an attempt to investigate the effect of curcumin on OXA resistance in CRC, OXA-resistant cell line HCT116/OXA was established firstly. The effect of curcumin on cell proliferation was evaluated by MTT assay and Ki67 immunofluorescence staining, respectively. Cell apoptosis was evaluated by flow cytometry. In addition, transwell assay was used to detect the effect of curcumin on cell invasion and the activation of TGF-β/Smad signaling was examined by immunofluorescence and Western blot. Moreover, the therapeutic potential of curcumin was further examined in vivo using a CRC animal model. Results: The OXA-resistant cell line HCT116/OXA was successfully established, and combination of OXA with curcumin reduced OXA resistance in vitro. Besides, the combination treatment inhibited the expressions of p-p65 and Bcl-2, but increased the level of active-caspase3. In addition, curcumin inhibited EMT via regulation of TGF-β/Smad2/3 signaling pathway. Moreover, in vivo study confirmed curcumin could reverse OXA resistance in CRC. Conclusion: Our study indicated that curcumin could reserve OXA resistance in CRC through dampening TGF-β/Smads signaling in vitro and in vivo.