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With economic progression in China, Yellow River Basin serves as a critical economic belt, which has also been recognized as a cradle of Chinese culture. A watershed is a complex structure of social, economic, and natural factors, and the diversity of its components determines its complexity. Studies on the spatiotemporal distribution characteristics and factors influencing the tourism eco-efficiency at the watershed scale are crucial for the sustainable regional socio-economic development, maintaining a virtuous cycle of various ecosystems, and comprehensively considering the utilization and coordinated development of various elements. Based on tourism eco-efficiency, the coordination degree of regional human–land system and the sustainable development levels can be accurately measured. With the tourism eco-efficiency in the Yellow River Basin from 2009 to 2019, the present study considers 63 cities in the Yellow River Basin as the research area by adopting the super-efficiency slacks-based measure (Super-SBM) model. Methods such as trend surface analysis, spatial autocorrelation analysis, elliptic standard deviation analysis, and hot spot analysis were used to explore their spatiotemporal distribution and evolution characteristics. The geographical and temporal weighted regression (GTWR) model was used to determine the factors influencing the tourism eco-efficiency value. The findings are as follows: ①The level of tourism eco-efficiency in the Yellow River Basin is not high, exhibiting a fluctuating upward trend. ②The tourism eco-efficiency in the Yellow River Basin shows significant spatial interdependence and agglomeration. Furthermore, the track of the center of gravity moves from northeast to southwest. ③ The tourism eco-efficiency in the Yellow River Basin is affected by various factors, with the economic development level having the greatest influence. [ABSTRACT FROM AUTHOR]

The purpose of this work was to illustrate the effect of processing with vinegar on saikosaponins of Bupleurum chinense DC. (BC) and the protective effects of saikosaponin A (SSA), saikosaponin b1 (SSb1), saikosaponin b2 (SSb2), and saikosaponin D (SSD) in lipopolysaccharide (LPS)-induced acute lung injury (ALI) mice. We comprehensively evaluated the anti-inflammatory effects and potential mechanisms of SSA, SSb1, SSb2, and SSD through an LPS-induced ALI model using intratracheal injection. The results showed that SSA, SSb1, SSb2, and SSD significantly decreased pulmonary edema; reduced the levels of IL-6, TNF-α, and IL-1β in serum and lung tissues; alleviated pulmonary pathological damage; and decreased the levels of the IL-6, TNF-α, and IL-1β genes and the expression of NF-κB/TLR4-related proteins. Interestingly, they were similar in structure, but SSb2 had a better anti-inflammatory effect at the same dose, according to a principal component analysis. These findings indicated that it may not have been comprehensive to only use SSA and SSD as indicators to evaluate the quality of BC, especially as the contents of SSb1 and SSb2 in vinegar-processed BC were significantly increased. [ABSTRACT FROM AUTHOR]

Orchids are the flowers of magnetic beauty. Vivid and attractive flowers with magnificent shapes make them the king of the floriculture industry. However, the long-awaited flowering is a drawback to their market success, and therefore, flowering time regulation is the key to studies about orchid flower development. Although there are some rare orchids with a continuous flowering pattern, the molecular regulatory mechanisms are yet to be elucidated to find applicable solutions to other orchid species. Multiple regulatory pathways, such as photoperiod, vernalization, circadian clock, temperature and hormonal pathways are thought to signalize flower timing using a group of floral integrators. This mini review, thus, organizes the current knowledge of floral time regulators to suggest future perspectives on the continuous flowering mechanism that may help to plan functional studies to induce flowering revolution in precious orchid species. [ABSTRACT FROM AUTHOR]

The TIFY gene family (formerly known as the zinc finger proteins expressed in inflorescence meristem (ZIM) family) not only functions in plant defense responses but also are widely involved in regulating plant growth and development. However, the identification and functional analysis of TIFY proteins remain unexplored in Orchidaceae. Here, we identified 19 putative TIFY genes in the Phalaenopsis aphrodite genome. The phylogenetic tree classified them into four subfamilies: 14 members from JAZ, 3 members from ZML, and 1 each from PPD and TIFY. Sequence analysis revealed that all Phalaenopsis TIFY proteins contained a TIFY domain. Exon–intron analysis showed that the intron number and length of Phalaenopsis TIFY genes varied, whereas the same subfamily and subgroup genes had similar exon or intron numbers and distributions. The most abundant cis-elements in the promoter regions of the 19 TIFY genes were associated with light responsiveness, followed by MeJA and ABA, indicating their potential regulation by light and phytohormones. The 13 candidate TIFY genes screened from the transcriptome data exhibited two types of expression trends, suggesting their different roles in cell proliferation and cell expansion of floral organ growth during Phalaenopsis flower opening. Overall, this study serves as a background for investigating the underlying roles of TIFY genes in floral organ growth in Phalaenopsis. [ABSTRACT FROM AUTHOR]

Aim/Background: We investigated the composition and structure of intracellular polysaccharides in cucumber seeds (CSs) and their effect on Sprague-Dawley (SD) rats and potential activity for fracture healing. Materials and Methods: Polysaccharides are its main water-soluble active ingredient. The SD rat tibia fracture model was established by surgical method, and the healing effect of cucumber seed polysaccharides (CSPs) on SD rat tibia fracture was preliminarily explored. Through histopathological observation, determination of rat serum indicators alkaline phosphatase (AKP), acid phosphatase (ACP), BGP, X-ray imaging observation, and micro-Computed Tomography (CT) imaging observation at different periods. Results and Conclusion: The results showed that CSP enhanced the activity of osteoblasts, increased the metabolic rate of osteoclasts, increased the secretion of AKP, BGP, and ACP, shortened the fracture healing time of SD rats and effectively promoted the healing of tibial fractures in SD rats. [ABSTRACT FROM AUTHOR]

Aim: We aimed to optimize the steaming process of Pana notoginseng using response surface methodology (RSM). Materials and Methods: The yield and immune activity of steamed P. notoginseng polysaccharides (s-PNPs) was used as the indicators to optimize the steaming parameters: wetting time, steaming time, and temperature. After this, chromatogram and spectroscopy were used to analyze the effect of steaming on the structure of polysaccharides. Then, our study evaluated the immunological activities between s-PNPs and raw P. notoginseng polysaccharides (r-PNPs) in vivo and in vitro. Results: The optimal parameters of processing technology were as follows: wetting time was 25 h, steaming time was 4 h, and steaming temperature was 110°C. The s-PNPs yield reached a maximum of 13.67 ± 0.39%, and the cell proliferation rate was 22.87 ± 0.015% under these conditions. The chemical analysis method showed that the polysaccharide content was slightly increased, the protein content was decreased and the monosaccharide composition analysis indicated that the glucose content in s-PNPs was significantly increased than r-PNPs. Moreover, Fourier transform infrared spectroscopy analysis showed that the functional groups of polysaccharides changed partially between s-PNPs and r-PNPs. In addition, the immunological activity of s-PNPs was better than that of r-PNPs in vivo and in vitro. Conclusion: These studies showed that polysaccharides content was increased, and the immune function of s-PNPs was enhanced after applying steaming, making this approach meaningful for the development and application of P. notoginseng with its immunomodulatory. [ABSTRACT FROM AUTHOR]

Heat shock factors (HSFs) are the key regulators of heat stress responses and play pivotal roles in tissue development and the temperature-induced regulation of secondary metabolites. In order to elucidate the roles of HSFs in Cymbidium ensifolium, we conducted a genome-wide identification of CeHSF genes and predicted their functions based on their structural features and splicing patterns. Our results revealed 22 HSF family members, with each gene containing more than one intron. According to phylogenetic analysis, 59.1% of HSFs were grouped into the A subfamily, while subfamily HSFC contained only two HSFs. And the HSF gene families were differentiated evolutionarily between plant species. Two tandem repeats were found on Chr02, and two segmental duplication pairs were observed on Chr12, Chr17, and Chr19; this provided evidence for whole-genome duplication (WGD) events in C. ensifolium. The core region of the promoter in most CeHSF genes contained cis-acting elements such as AP2/ERF and bHLH, which were associated with plant growth, development, and stress responses. Except for CeHSF11, 14, and 19, each of the remaining CeHSFs contained at least one miRNA binding site. This included binding sites for miR156, miR393, and miR319, which were responsive to temperature and other stresses. The HSF gene family exhibited significant tissue specificity in both vegetative and floral organs of C. ensifolium. CeHSF13 and CeHSF15 showed relatively significant expression in flowers compared to other genes. During flower development, CeHSF15 exhibited markedly elevated expression in the early stages of flower opening, implicating critical regulatory functions in organ development and floral scent-related regulations. During the poikilothermic treatment, CeHSF14 was upregulated over 200-fold after 6 h of heat treatment. CeHSF13 and CeHSF14 showed the highest expression at 6 h of low temperature, while the expression of CeHSF15 and CeHSF21 continuously decreased at a low temperature. The expression patterns of CeHSFs further confirmed their role in responding to temperature stress. Our study may help reveal the important roles of HSFs in plant development and metabolic regulation and show insight for the further molecular design breeding of C. ensifolium. [ABSTRACT FROM AUTHOR]

Auxin Response Factors (ARFs) mediate auxin signaling and govern diverse biological processes. However, a comprehensive analysis of the ARF gene family and identification of their key regulatory functions have not been conducted in Melastoma dodecandrum, leading to a weak understanding of further use and development for this functional shrub. In this study, we successfully identified a total of 27 members of the ARF gene family in M. dodecandrum and classified them into Class I–III. Class II–III showed more significant gene duplication than Class I, especially for MedARF16s. According to the prediction of cis-regulatory elements, the AP2/ERF, BHLH, and bZIP transcription factor families may serve as regulatory factors controlling the transcriptional pre-initiation expression of MedARF. Analysis of miRNA editing sites reveals that miR160 may play a regulatory role in the post-transcriptional expression of MeARF. Expression profiles revealed that more than half of the MedARFs exhibited high expression levels in the stem compared to other organs. While there are some specific genes expressed only in flowers, it is noteworthy that MedARF16s, MedARF7A, and MedARF9B, which are highly expressed in stems, also demonstrate high expressions in other organs of M. dodecandrum. Further hormone treatment experiments revealed that these MedARFs were sensitive to auxin changes, with MedARF6C and MedARF7A showing significant and rapid changes in expression upon increasing exogenous auxin. In brief, our findings suggest a crucial role in regulating plant growth and development in M. dodecandrum by responding to changes in auxin. These results can provide a theoretical basis for future molecular breeding in Myrtaceae. [ABSTRACT FROM AUTHOR]

Gamma (γ)-ray irradiation is one of the important modern breeding methods. Gamma-ray irradiation can affect the growth rate and other characteristics of plants. Plant growth rate is crucial for plants. In horticultural crops, the growth rate of plants is closely related to the growth of leaves and flowering time, both of which have important ornamental value. In this study, 60Co-γ-ray was used to treat P. equestris plants. After irradiation, the plant's leaf growth rate increased, and sugar content and antioxidant enzyme activity increased. Therefore, we used RNA-seq technology to analyze the differential gene expression and pathways of control leaves and irradiated leaves. Through transcriptome analysis, we investigated the reasons for the rapid growth of P. equestris leaves after irradiation. In the analysis, genes related to cell wall relaxation and glucose metabolism showed differential expression. In addition, the expression level of genes encoding ROS scavenging enzyme synthesis regulatory genes increased after irradiation. We identified two genes related to P. equestris leaf growth using VIGS technology: PeNGA and PeEXPA10. The expression of PeEXPA10, a gene related to cell wall expansion, was down-regulated, cell wall expansion ability decreased, cell size decreased, and leaf growth rate slowed down. The TCP-NGATHA (NGA) molecular regulatory module plays a crucial role in cell proliferation. When the expression of the PeNGA gene decreases, the leaf growth rate increases, and the number of cells increases. After irradiation, PeNGA and PeEXPA10 affect the growth of P. equestris leaves by influencing cell proliferation and cell expansion, respectively. In addition, many genes in the plant hormone signaling pathway show differential expression after irradiation, indicating the crucial role of plant hormones in plant leaf growth. This provides a theoretical basis for future research on leaf development and biological breeding. [ABSTRACT FROM AUTHOR]

Though conserved in higher plants, the WOX transcription factors play crucial roles in plant growth and development of Melastoma dodecandrum Lour., which shows pioneer position in land ecosystem formation and produces nutritional fruits. Identifying the WOX family genes in M. dodecandrum is imperative for elucidating its growth and development mechanisms. However, the WOX genes in M. dodecandrum have not yet been characterized. In this study, by identification 22 WOX genes in M. dodecandrum based on current genome data, we classified family genes into three clades and nine types with homeodomains. We highlighted gene duplications of MedWOX4, which offered evidences of whole-genome duplication events. Promoter analysis illustrated that cis-regulatory elements related to light and stress responses and plant growth were enriched. Expression pattern and RT-qPCR results demonstrated that the majority of WOX genes exhibited expression in the stem. MedWOX13s displayed highest expression across various tissues. MedWOX4s displayed a specific expression in the stem. Collectively, our study provided foundations for elucidating WOX gene functions and further molecular design breeding in M. dodecandrum. [ABSTRACT FROM AUTHOR]

Despite extensive research on orchid reproductive strategies, the genetic studies of sex differentiation in the orchid family are still lacking. In this study, we compared three sexual phenotypes of Cymbidium tortisepalum bisexual flowers as well as female and male unisexual mutants. Through comparative transcriptomes, we analyzed the sex-biased differentially expressed genes (DEGs) and gene co-expression networks of sex organs (gynostemium and ovary) among them, identified the candidate genes of sex differentiation, and validated their expression by qRT-PCR. The C. tortisepalum unisexual mutants with degenerated phenotypes were compared to the bisexual plants with respect to both the flower organs and plant morphologies. Totally, 12,145, 10,789, and 14,447 genes were uniquely expressed in the female, male, and hermaphrodite sex organs, respectively. A total of 4291 sex-biased DEGs were detected among them, with 871, 2867, and 1937 DEGs in the comparisons of bisexual vs. female, bisexual vs. male, and male vs. female flowers, respectively. Two co-expressed network modules, with 81 and 419 genes were tightly correlated with female sexual traits, while two others with 265 and 135 genes were highly correlated with male sexual traits. Two female-biased hub genes (CtSDR3b and CtSDR3b-like) nested in the female modules, the homologs of maize sex determinant tasselseed2, may control the feminization of C. tortisepalum. At the same time, two male-biased hub genes (CtYAB2 and CtYAB5) nested in the male modules, the homologs of grape sex determinant VviYABBY3, may control the androphany of C. tortisepalum. This study discovered the molecular regulation networks and proposed a model for orchid sex differentiation, therefore providing for the first time the genetic basis for the sex separation in the orchid family. [ABSTRACT FROM AUTHOR]

AP2/ERF transcription factors play crucial roles in various biological activities, including plant growth, development, and responses to biotic and abiotic stressors. However, limited research has been conducted on the AP2/ERF genes of Melastoma dodecandrum for breeding of this potential fruit crop. Leveraging the recently published whole genome sequence, we conducted a comprehensive assessment of this superfamily and explored the expression patterns of AP2/ERF genes at a genome-wide level. A significant number of genes, totaling 218, were discovered to possess the AP2 domain sequence and displayed notable structural variations among five subfamilies. An uneven distribution of these genes was observed on 12 pseudochromosomes as the result of gene expansion facilitated by segmental duplications. Analysis of cis-acting elements within promoter sites and 87.6% miRNA splicing genes predicted their involvement in multiple hormone responses and abiotic stresses through transcriptional and post-transcriptional regulations. Transcriptome analysis combined with qRT-PCR results indicated that certain candidate genes are involved in tissue formation and the response to developmental changes induced by IAA hormones. Overall, our study provides valuable insights into the evolution of ERF genes in angiosperms and lays a solid foundation for future breeding investigations aimed at improving fruit quality and enhancing adaptation to barren land environments. [ABSTRACT FROM AUTHOR]

WRKY is one of the largest transcription factor families in plants and plays an important role in plant growth and development as well as in abiotic and biological stresses. However, there is little information about the WRKY family in Melastoma dodecandrum. In this study, 126 WRKY members were identified in M. dodecandrum. According to phylogenetic analysis, they were divided into three major groups, and group II was further divided into five subgroups. MedWRKY genes were unevenly distributed on 12 chromosomes. Additionally, the gene structure and sequence composition were similar within the same group and differed between groups, suggesting their functional diversity. The promoter sequence analysis identified a number of cis-acting elements related to plant growth and development, stress response, and secondary metabolite synthesis in the WRKY gene family. The collinearity analysis showed that gene replication events were the main driving force of MedWRKY gene evolution. The transcriptome data and RT-qPCR analysis suggested that MedWRKY genes had higher expression in the roots and ripe fruit of M. dodecandrum. In short, this paper lays a foundation for further study of the functions and molecular mechanism of M. dodecandrum WRKY gene family. [ABSTRACT FROM AUTHOR]

Aerides Lour. (Orchidaceae, Aeridinae) is a group of epiphytic orchids with high ornamental value, mainly distributed in tropical and subtropical forests, that comprises approximately 20 species. The species are of great value in floriculture and garden designing because of their beautiful flower shapes and colors. Although the morphological boundaries of Aerides are clearly defined, the relationship between Aerides and other closely related genera is still ambiguous in terms of phylogeny. To better understand their phylogenetic relationships, this study used next-generation sequencing technology to investigate the phylogeny and DNA barcoding of this taxonomic unit using genetic information from six Aerides plastid genomes. The quadripartite-structure plastomes ranged from 147,244 bp to 148,391 bp and included 120 genes. Among them, 74 were protein coding genes, 38 were tRNA genes and 8 were rRNA genes, while the ndh genes were pseudogenized or lost. Four non-coding mutational hotspots (rpl20–rpl33, psbM, petB, rpoB–trnCGCA, Pi > 0.06) were identified. A total of 71–77 SSRs and 19–46 long repeats (>30 bp) were recognized in Aerides plastomes, which were mostly located in the large single-copy region. Phylogenetic analysis indicated that Aerides was monophylic and sister to Renanthera. Moreover, our results confirmed that six Aerides species can be divided into three major clades. These findings provide assistance for species identification and DNA barcoding investigation in Aerides, as well as contributes to future research on the phylogenomics of Orchidaceae. [ABSTRACT FROM AUTHOR]

The genus Oxalis contains important species worldwide with great economic and edible values. However, the testing guidelines have not been furbished, especially in China. Oxalis germplasm, including 60 species and 125 varieties, was collected from home and abroad and extensive field trials and phenotypic observations were conducted along with quantitative taxonomy, observations, correlation analysis and cluster analysis. Under the test guidelines of the International Union for the Protection of New Plant Varieties (UPOV), general guidelines for testing for distinctness, uniformity, stability (DUS) of new plant varieties, and Japanese test guidelines for DUS of Oxalis , 96 test characteristics (38 qualitative characteristics, 28 quantitative characteristics and 30 pseudo-qualitative characteristics) were determined as DUS test characteristics of Oxalis. Each test characteristic was scientifically graded and accurately described, and standard varieties and characteristic diagrams were provided for some characteristics. The guidelines for testing DUS of new plant varieties of Oxalis provide a standard for examining and testing new varieties of plants. [ABSTRACT FROM AUTHOR]

Paraphalaenopsis, a genus of perennial herbs from the family Orchidaceae, contains a number of ornamental species. However, there is no information on the chloroplast genomes of Paraphalaenopsis, which limits our studies of this genus. In this study, we reported the chloroplast genomes of three species of Paraphalaenopsis (P. labukensis, P. denevel, and P. laycockii 'Semi-alba') and performed comprehensive comparative analysis. These three chloroplast genomes showed a typical quadripartile structure. Their lengths ranged from 147,311 bp to 149,240 bp. Each genome contained 120 unique genes, including 74 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Comparative analysis revealed major differences in sequence divergence in the three chloroplast genomes. In addition, six hypervariable regions were identified (psbM-trnDGUC, psbB, ccsA, trnKUUU, trnSGCU-trnGUCC, rps16-trnQUUG) that can be used as DNA molecular markers. Phylogenetic relationships were determined using the chloroplast genomes of 28 species from 12 genera of Aeridinae. Results suggested that Paraphalaenopsis was a clade of Aeridinae that was sister to the Holcoglossum-Vanda clade, with 100% bootstrap support within Aeridinae. The findings of this study provided the foundation for future studies on the phylogenetic analysis of Aeridinae. [ABSTRACT FROM AUTHOR]

Human beings have disturbed the original characters of plants through interspecies hybridization, especially for economically producing cultivars with enhanced traits. Phalaenopsis is remoulded for exquisite flowers with huge shape and popular colors. However, the current challenge in Phalaenopsis breeding is that existing varieties tend to lose their original floral scent during the complex process of super-paraent hybridization. To address this, we collected a wide range of native species and hybrids to form the composition background and correlated the dynamics of Phalaenopsis fragrance for the futher breeding. A total of 208 volatile organic compounds (VOCs), with 83 prominent compounds constituting about 40 % of the identified substances. The primary species included all three major classes of floral fragrance compounds, with native species accounting for 83.33 % of volatile compounds released at levels exceeding 100 ng g−1 h−1. Both primary species and cultivars exhibited distinct aroma profiles, characterized by ten specific substances. Phalaenopsis stobartiana , originating from China, shows potential for benzenoid scents in fragrant flower breeding. On the other hand, hybrids primarily consisted of terpenoids and contained a higher abundance of low-threshold floral fragrance compounds. We also observed significant correlations between terpenoid and benzenoid scents with respect to color and flower shape. The height and width of the plants also showed a significant negative correlation with phenylpropanoid/ benzenoids and nitrogen-containing scent compounds. By conducting an extensive investigation into floral fragrance detection, we were able to concisely present the interrelationships among various characteristics of Phalaenopsis. This endeavor lays a primary foundation for exploring polymorphism in floral scent, providing guidance in Phalaenopsis breeding and facilitating ongoing genome-based molecular design for cultivating high-quality and fragrant orchids. [Display omitted] • Primary species and cultivars exhibited distinct aroma profiles separated by ten main characteristic substances. • Metabolic shunting and hybridization origin are possible reasons for the loss of floral fragrances in Phalaenopsis cultivars. • Phalaenopsis stobartiana can be prospective parent to make up for the benzenoid floral substances of Phalaenopsis. [ABSTRACT FROM AUTHOR]

Melastoma dodecandrum is recognized as an ideal industrial subshrub in Melastoma with special characters, like medicinal component, edible fruits, bizarre heteromorphic stamen flowers. Because of strong tolerance to drought and poor land, now it is gradually domesticated into functional economic crops. These special development characters and reported abundant metabolites are suspected to have influence by the mitochondria. To get a better understand of this potential species, we first generated the circle mitochondrial genome with Pacbio-Illumina hybrid sequencing strategy. Finally, the 411,944 bp physical map of M. dodecandrum displayed a long intergenic region segmentation structure and from the comparison with other plant mitogenomes, we unveiled large-scale rearrangements of conserved genes caused by micro inversions. A new insight highlighted the lateral gene transfer from nuclear, chloroplast to mitochondrial genome, consistent fragments captured functional genes like Cytb6f. In the generalized analysis of energy and metabolism genes, we detected a loss of ccmFN and a repeat of cox1 in the whole mitogenome, making it contain relatively complete energy metabolic system. Abnormal selective pressure occurred among the genes in mitogenome and chloroplast, inferring different driving forces of selection existed in the transfer of organic and nuclear genetic materials from hybridization event. This manifested a phylogenetic conflict between the mitochondrial gene and chloroplast gene tree. Eventually, our newly assembled mitogenome will add the knowledge of general trends in mitogenome evolution within dicotyledons and lay solid foundation to the future industrial development. • The reference mitochondrial genome of Melastoma dodecandrum marked large-scale rearrangements of conserved genes and lateral gene transfer [ABSTRACT FROM AUTHOR]

• Cymbidium orchids are the most valuable flowers with a long vegetative phase (2–3 years). • We obtained leafless flowers for three Cymbidium species through a special media combination in tissue culture. These can be excellent resources to study abiotic stress tolerance. • Comparative transcriptome between leafless flowers and healthy leaves provides important clues about melatonin-mediated flowering, which has not been documented before in orchids. • A number of DEGs were found for Tryptophan pathway with contrasting expression patterns between leafless flowers and healthy leaves of three Cymbidium species. Abiotic stress is a major constraint in the successful growth and development of ornamental plants under severe conditions. Since antiquity, melatonin homeostasis has been an effective contrivance in the strategies of abiotic stress tolerance in plants, although it is completely neglected in orchids, the champagne of flowers. Orchids with exceptionally long vegetative phase face a number of stresses and, therefore, stress alleviation has been a hot topic in orchid cultivation. The in-vitro flowering is a useful method for early identification of hybrids in crop improvement programs. We successfully achieved in-vitro leafless flowering in three Cymbidium orchids (C. sinense, C. goeringii and C. ensifolium), which are elite flowers in terms of versatile flower shapes, esthetic preference and price. Transcriptomic analysis was performed to compare the leafless flowers with leaves to identify genes related to tryptophan pathway and melatonin biosynthesis. More than 50 differentially expressed genes (DEGs) were identified in each species with contrasting expressions in the leafless flowers and leaves. The important melatonin pathway genes included serotonin N-acetyltransferase (SNAT), caffeic acid 3-O-methyltransferase (CAMT) and tryptophan decarboxylase (TDC). Moreover, clustering analysis pointed out the significant abiotic stress tolerance-related genes. This opening report, thus, provides a robust cradle to idealize the melatonin as an effective abiotic stress regulator to aid the long journey of vegetative growth and then flowering in precious orchids. [ABSTRACT FROM AUTHOR]

Melastoma dendrisetosum (Melastomataceae) was first reported in 1983. Chen & Henner (2007) merged it within M. sanguineum. In order to clarify the difference between the two and the taxonomic status of M. dendrisetosum, a field investigation, herbarium survey, and an examination of morphological and micromorphological characteristics were performed. M. dendriselosurn was confirmed as a distinct species, obviously different from M. sanguineurn. This species is narrowly endemic and extremely endangered. The study provides the latest morphological description of M.dendrisetosum, and lays a foundation for the precise identification and future conservation of this species. [ABSTRACT FROM AUTHOR]

Ecotypes are the result of ecological differentiation at the early stages of speciation. Adaptation to soil conditions offers arguably the best examples of local adaptation in plants. Two sympatric ecotypes, with either a red or green abaxial leaf surface, were found without clear geographical isolation in Phalaenopsis pulcherrima, a Southeast Asia endemic and endangered orchid. The soil of the red leaf ecotype has a higher water content and nutrient content than the green ecotype. What is the genetic structure of the two ecotypes? Is there complete or partial reproductive isolation between the two ecotypes? In this work, leaf reflection of the two ecotypes in P. pulcherrima were compared, to illustrate their difference in leaf color. The genetic differentiation between two ecotypes was examined, using ISSR and SRAP markers to determine the genetic structure of the populations. Our results showed that the green ecotype had reflectance spectrum peaks at 530 nm and 620 nm, while in the red ecotype, the peak at 530 nm was absent. A total of 165 ISSR and SRAP loci showed a high level of genetic diversity within the green ecotype, and analyses of the population structure revealed two genetic clusters that corresponded to the red and green ecotypes. The percentage of variation between the two ecotypes (24.55%) was greater than the percentage of variation among the populations (16.54%)—indicating partial reproductive isolation, high genetic differentiation, and that ecological differentiation has been more important than geographical barriers among populations within ecotypes. Most pairwise FST values between the populations within either ecotype on Hainan Island were less than 0.15; however, the FST between both the Thai and Malaysian populations and the Hainan Island population was greater than 0.25, due to South China sea isolation. Ecotypic differentiation is an important part of speciation; therefore, we must take into account the axes along which lineages sort, when formulating protection strategies. [ABSTRACT FROM AUTHOR]