Dove Tree Research Articles

Young dove trees tend to invest more biomass in vegetative and reproductive organs than old trees at the twig level

Research on the functional traits of twigs is of great significance to clarify the plant life-history strategies, especially for endangered plants. However, little attention has been given to the environmental adaptation strategy of different age twigs. The dove tree (Davidia involucrata Baill.), a relict and critically endangered Chinese species, was employed as a model species. Total lamina mass and area, stem mass and length, total bract mass and area, and total petiole mass were measured for 100 current-year terminal twigs (50 per age group) from old and young dove trees in Pingwu County, Sichuan, southwest China. Then, the scaling relationships within the twig were determined using the standardized major axis (SMA) regression method. Our results showed that the significantly positive correlations among traits of D. involucrata twigs, and scaling relationships between these traits are different between the two age groups. At the twig level, isometric scaling relationships exist between stem mass and lamina size (or bract size) and between total lamina mass and total lamina area (or total petiole mass). In contrast, allometric scaling relationships exist between lamina size (total mass and area) and stem length (with a common slope > 1), and between total lamina mass and total petiole mass (with a common slope < 1). For a given stem mass, stem length and bract area, young trees have larger total lamina mass and total bract mass, larger total lamina mass and area, and larger total bract mass than old trees, respectively. The results suggest that young trees tend to have more vegetative and reproductive organ mass per unit of supporting organ mass than old trees to meet their rapid growth needs.

Effects of water extract from Cornus controversa on the expression levels of DiSOC1-b and DiCCoAOMT1 genes related with the growth of dove tree seedlings

Abstract Although characterization of plant interactions has become a research hotspot to assess the adaptability of endangered plants, the underlying molecular basis remains elusive. Dove tree (Davidia involucrata) seedlings were watered with distilled water (CK), leaf water extract (0.025 g mL−1) and branch water extract (0.1 g mL−1) from Cornus controversa, respectively. Subsequently, the morphology, biomass and gene expression levels of DiSOC1-b and DiCCoAOMT1 were analyzed. The results showed that morphological traits and biomass accumulation of D. involucrata seedlings were decreased by the addition of leaf water extracts, and increased by branch water extracts. Moreover, the gene expression level of DiSOC1-b was significantly down-regulated, while the gene expression level of DiCCoAOMT1 was significantly up-regulated in the stems and roots of D. involucrata upon treatment with leaf water extracts of C. controversa. In contrast, the gene expression level of DiSOC1-b was significantly up-regulated in the leaves and stems, while the gene expression level of DiCCoAOMT1 was significantly down-regulated in the roots of D. involucrata upon treatment with branch water extracts of C. controversa. In addition, the expression level of DiSOC1-b was positively correlated with most of morphological traits and total biomass (P &amp;lt; 0.05), while DiCCoAOMT1 was negatively correlated with the majority of morphological traits in D. involucrata seedlings (P &amp;lt; 0.05). Taken together, these results suggest that water extracts from the leaves and branches of the C. controversa exhibit opposite allelopathic effects and affect the expression levels of genes related to growth (DiSOC1-b) and environmental adaptability (DiCCoAOMT1) in D. involucrata seedlings.

Cryptic divergences and repeated hybridizations within the endangered “living fossil” dove tree (Davidia involucrata) revealed by whole genome resequencing

The identification and understanding of cryptic intraspecific evolutionary units (lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species. However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range. Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories.

Overexpression of a laccase gene, DiLAC17, from Davidia involucrata causes severe seed abortion in Arabidopsis

Seed abortion is a common phenomenon in woody plants, especially in rare and endangered species. Serious seed abortion occurs in the dove tree and largely restricts its natural reproduction. A number of differentially expressed genes (DEGs) between normal and aborted seeds of the dove tree have been previously identified through transcriptome profiling. Among these, most DEGs encoding laccase showed significant upregulation in the aborted seeds. In this study, the laccase gene with the highest expression level in aborted seeds, DiLAC17, was cloned from the dove tree genome and further verified. Overexpression of the DiLAC17 gene in Arabidopsis resulted in retarded growth, deformed siliques, and severe seed abortion. Most Arabidopsis genes involved in seed development, such as AtLEC2, AtANT1, and AtRGE1, were suppressed in the transgenic lines. Laccase activity and lignin content were significantly improved in transgenic lines under ectopic overexpression of the DiLAC17 gene. Excessive lignin accumulation in the early developmental stage was assumed to be a key cause of restricting silique growth and seed expansion, which ultimately led to seed abortion. These results indicate a laccase-mediated pathway for seed abortion, which might be a strategy adopted by this rare and endangered species to reduce the reproductive load.

First report of Mesoptyelus nigrifrons on the dove tree (Davidia involucrata Baill.) in China

First report of Mesoptyelus nigrifrons on the dove tree (Davidia involucrata Baill.) in China

Overexpression of an autophagy-related gene DiATG3 from Davidia involucrata improves plant thermotolerance by enhancing the accumulation of polyamines and regulating genes in calcium and MAPK signaling pathways

Autophagy, a conserved eukaryotic mechanism for degrading intracellular constituents, plays prominent roles in plant abiotic stress tolerance. This study aimed to isolate an autophagy-related gene DiATG3 from a cool-adapted endangered plant species, dove tree (Davidia involucrata Baill.), and to investigate the physiological functions and regulatory mechanisms of DiATG3 for improving heat tolerance. DiATG3 was found to mainly localize to cytoplasm and possess the N-terminal domain, the catalytic domain with the HPC motif, and the C-terminal domain with the FLKF motif. Elevated transcript level of DiATG3 was detected in D. involucrata treated with heat stress. The constitutive overexpression of DiATG3 in Arabidopsis led to elevated levels of autophagy and conferred tolerance under heat stress. Furthermore, this thermotolerant phenotype was associated with improved photosynthetic capacity, higher antioxidant enzyme activities, and increased accumulation of polyamines. Transcriptome analysis suggest that activated calcium signaling and mitogen-activated protein kinase (MAPK) cascade may act as a central hub necessary for DiATG3-mediated heat tolerance. In addition, DiATG3 overexpression resulted in up-regulated expression of stress-related genes including heat shock factor A3 (AtHSFA3), dehydration-responsive element-binding protein 2C (AtDREB2C), AtWRKY26, and AtWRKY33 after heat treatment. Our study could yield insights into the engagement of plant autophagy during abiotic stress responses and contribute to breeding and engineering thermotolerant endangered plant species.

Twigs of dove tree in high-latitude region tend to increase biomass accumulation in vegetative organs but decrease it in reproductive organs.

Adaptive traits are an important dimension for studying the interactions between rare plants and environment. Although the endangered mechanism of rare plants has been reported in many studies, how their twigs adapt to heterogeneous environments associated with latitude is still poorly known. Dove tree (Davidia involucrata Baill.), a monotypic rare species in China, was employed as a model species in our study, and the differences in functional traits, growth relationships and resource allocation among components of annual twig were investigated in three latitudinal regions (32°19' N, 30°08' and 27°55') in the Sichuan, Southwest China. Compared with low- and middle-latitude regions, the twig diameter in high-latitude region decreased by 36% and 26%, and dry mass decreased by 32% and 35%, respectively. Moreover, there existed an allometric growth between flower mass and stem mass or leaf mass in high-latitude region but an isometric growth in low- and middle-latitude regions. At the flower level, an isometric growth between bract area and flower stalk mass was detected among in three latitudinal regions, and the flower stalk mass in the low-latitude region was higher than in the middle- and high-latitude regions for a given bract area and flower mass. At the leaf level, the growth rate of petiole mass was significantly higher than those of leaf area, lamina mass and leaf mass among three latitudinal regions, and the petiole mass in the low-latitude region was higher than in the other two regions for a given leaf mass. Our research demonstrated that the twigs of dove tree in high-latitude region tend to become smaller, and resource input increase in stems and leaves but decrease in flowers, which reflects that dove tree can adapt to the environmental changes across different latitudes by adjusting phenotypic traits growth and biomass allocation of twigs.

Increasing Lignin Accumulation in Arabidopsis and Poplar by Overexpressing a CCoAOMT Gene from the Dove Tree (Davidia involucrata Baill.)

Increasing Lignin Accumulation in Arabidopsis and Poplar by Overexpressing a CCoAOMT Gene from the Dove Tree (Davidia involucrata Baill.)

First Report Davidia involucrate Baill Leaf Blight Caused by Nigrospora oryzae in Sichuan, China.

Davidia involucrata Baill. (D. involucrate), also known as dove tree, is listed as the first class national protected plant in China and the only extant member of the Davidiaceae family (Fu & Jin 1992). Referred to by the terms 'living fossil' and 'giant panda' owing to its evolutionary status as a Tertiary relic and its native distribution, D. involucrate exhibits substantial ornamental and academic value (Fang & Song 1975; Wu et al. 2004). A small rounded head inflorescence beneath its big white bracts have a unique charm to catch people's attention, thus they were cultivated in many areas of the world as an ornamental plant (Claßen-Bockhoff & Arndt 2018). In September 2021, dove trees in Meigu country (N 28°33', E 103°14'), Sichuan Province, China were found to appear symptoms of leaf blight of unknown origin. This blight disease incidence was 90% in a survey of 30 D. involucrata trees. Early symptoms appeared as circular, necrotic tissue that developed into circular or irregular spots (FigS1. A). Five leaves exhibiting typical symptoms of this form of leaf blight were excised from the margin between diseased and healthy tissue. These pieces were then treated for 40 s with 75% ethanol for surface sterilization, followed by treatment with 5% NaClO for 2 min, rinsed then plated on potato dextrose agar (PDA) medium supplemented with carbenicillin and ampicillin (each 50 μg/mL), and incubated in the dark for 4 days at 28°C. Pure cultures were then prepared by transferring hyphal tips from the edges of these colonies onto fresh PDA plates, with isolate LW11 being selected as a representative isolate for causal pathogen characterization. These cultured colonies were initially white before turning grayish-black over time (FigS1. B). Conidia were single-celled, black, spherical or oblate and ranged from 10 - 16.0 μm in diameter (mean = 12.5 ± 0.43 μm, n = 40) (FigS1. C), with conidia being present at the tip of conidiophores on hyaline vesicles. These morphological traits were found to align well with those of Nigrospora oryzae (Wang et al. 2017). To confirm this tentative identification, gDNA was extracted from isolate LW11, followed by the amplification of the internal transcribed spacer (ITS) region, beta-tubulin (TUB2), and translation elongation factor 1-alpha (TEF1) sequences with the respective ITS1/ITS4 (White et al., 1990), Bt-2a/Bt-2b (Glass & Donaldson 1995), and TEF1-728F/EF1-986R primer pairs (Carbone et al. 1999). Fragments of 577 bp, 442 bp, and 309 bp were obtained. A maximum likelihood bootstrapping approach (1000 bootstrap replicates) was used to construct a phylogenetic tree based on a combination of the ITS, TUB, and TEF1-α sequences, indicating that isolate LW11 clustered with other N. oryzae isolates (FigS2). The ITS, TUB, and TEF1-α sequences from isolate LW11 were deposited in GenBank with the accession numbers OL659284, OL685345, and OL685347, respectively. The pathogenicity test was performed by detached D. involucrate leaves with mycelial plugs, with the other half instead being inoculated using pure agar plugs as a negative control. Following incubation for 5 days, black lesions were evident on leaves inoculated with mycelial plugs (FigS1. F; FigS1, DE) but not on control leaves (FigS1. F). This report is the first to our knowledge of D. involucrata leaf blight by N.oryzae in China or anywhere else in the world. Further research is thus needed to better manage the spread of this disease with the goal of protecting this living fossil species.

Inducing bract-like leaves in Arabidopsis through ectopically expressing an ASR gene from the dove tree

Bract, or inflorescence leaf, is cryptic in most model plants due to a conserved suppression mechanism. While, bract is present in some ornamental plants and plays an important role in their reproductive growth. The huge and long-standing bract of an ancient species, the dove tree (Davidia), implies the existence of a distinctive pathway of bract development. However, compared to bract suppression, little is known about the regulators during bract promoting. Here, a gene named DiASR1 involved into bract development regulation in Davidia is reported. During bract development, the expression profile of the DiASR1 gene was bract-specific, and increased along with the bract growth. The DiASR1 gene was activated by environmental cues including high temperature, strong light and abscisic acid, while inhibited by low temperature, dark, gibberellin. Remarkably, ectopic expression of the DiASR1 gene resulted in bract-like leaves, besides early flowering, abnormal floral development, and aborted pollens in transgenic Arabidopsis lines. The bract-like Arabidopsis leaves exhibited a similar fading process and cell architecture to those of Davidia bract. The ectopic induction of bract-like leaves confirmed the critical function of the DiASR1 gene for bract development, and provided new insights to understand the regulation mechanism underlying the process of leaf metamorphosis.

DiZF-C3H1, a zinc finger transcription factor from the dove tree (Davidia involucrata Baill.), plays a negative role in seed development and plant growth in Arabidopsis and tobacco

Low seed fertility seriously limits the survival and adaption of rare plant species. Here, we identified a seed-specific gene, DiZF-C3H1, from the dove tree and verified its function. Overexpression of DiZF-C3H1 caused retarded root development, delayed anthesis, abnormal floral organs, and deformed siliques in transgenic Arabidopsis lines. No offspring were obtained in transgenic Arabidopsis lines due to serious seed abortion. Therefore, we performed further verification in tobacco. Similarly, overexpression of DiZF-C3H1 retarded root development and reduced berry size and seed yield in transgenic tobacco lines. Moreover, although transgenic tobacco offspring were obtained, the viability of transgenic seeds was reduced and their germination was delayed. In addition, faded flowers were observed in transgenic tobacco lines. Taken together, DiZF-C3H1 was verified to play a negative role in root growth, floral organ development, and especially seed development in Arabidopsis and tobacco. This appears to be a deleterious gene for these model plants with high seed fertility. However, this function might be of special significance for Davidia, whose seed dormancy period is extremely long; DiZF-C3H1 might play a critical role in the distinctive reproduction strategy adopted by this rare and endangered species.

Whole genome re-sequencing reveals the genetic diversity and evolutionary patterns of Eucommia ulmoides.

Eucommia ulmoides (E. ulmoides) is a deciduous perennial tree belonging to the order Garryales, and is known as "living fossil" plant, along with ginkgo (Ginkgo biloba), metaspaca (Metasequoia glyptostroboides) and dove tree (Davidia involucrata Baill). However, the genetic diversity and population structure of E. ulmoides arestill ambiguous nowdays. In this study, we re-sequenced the genomes of 12 E. ulmoides accessions from different major climatic geography regions in China to elucidate the genetic diversity, population structure and evolutionary pattern. By integration of phylogenetic analysis, principal component analysis and population structure analysis based on a number of high-quality SNPs, a total of 12 E. ulmoides accessions were clustered into four different groups. This result is consistent with their geographical location except for group samples from Shanghai and Hunan province. E. ulmoides accessions from Hunan province exhibited a closer genetic relationship with E. ulmoides accessions from Shanghai in China compared with other regions, which is also supported by the result of population structure analyses. Genetic diversity analysis further revealed that E. ulmoides samples in Shanghai and Hunan province were with higher genetic diversity than those in other regions in this study. In addition, we treated the E. ulmoides materials from Shanghai and Hunan province as group A, and the other materials from other places as group B, and then analyzed the evolutionary pattern of E. ulmoides. The result showed the significant differentiation (Fst = 0.1545) between group A and group B. Some candidate highly divergent genome regions were identified in group A by selective sweep analyses, and the function analysis of candidate genes in these regions showed that biological regulation processes could be correlated with the Eu-rubber biosynthesis. Notably, nine genes were identified from selective sweep regions. They were involved in the Eu-rubber biosynthesis and expressed in rubber containing tissues. The genetic diversity research and evolution model of E. ulmoides were preliminarily explored in this study, which laid the foundation for the protection of germplasm resources and the development and utilization of multipurpose germplasm resources in the future.

Metabolome profiling of stratified seeds provides insight into the regulation of dormancy in Davidia involucrata

Dove tree (Davidia involucrata), a tertiary vestige species, is well-adapted to cool conditions. Dormancy in D. involucrata seed lasts for an extremely long period of time, typically between 3 and 4 years, and this characteristic makes the species an excellent model for studying the mechanisms of seed dormancy. The molecular mechanisms governing germination control in D. involucrata are still unknown. Seed stratification have been reported to enhance germination in recalcitrant seeds. We performed a widely targeted metabolome profiling to identify metabolites and associated pathways in D. involucrata seeds from six different moist sand stratification durations (0–30 months) using the ultra-high-performance liquid chromatography-Q Exactive Orbitrap-Mass spectrometry. There was an increasing germination rate with prolonged stratification durations (12–30 months). Furthermore, we detected 10,008 metabolites in the stratified seeds. We also detected 48 differentially accumulated metabolites (DAMs) between all stratification periods in the seeds, with 10 highly conserved metabolites. Most of the differentially accumulated metabolites between unstratified and stratified seeds were enriched in purine metabolism, pyrimidine metabolism, flavone and flavonol biosynthesis, phenylpropanoid biosynthesis, and arginine biosynthesis pathways. Key phytohormones, abscisic acid, indole-3 acetic acid, and sinapic acid were differentially accumulated in the seeds and are predicted to regulate dormancy in D. involucrata. We have provided extensive metabolic information useful for future works on dove tree germination study.

Investigation and Evaluation of Plant Resources Based on Modern Digital Rural Eecotourism Development

The establishment of natural ecological reserves has effectively protected the original ecological environment and natural resources to a certain extent. Bima Mountain Nature Reserve is rich in animal and plant resources. The main plants in the reserve are naturally growing subtropical evergreen broad-leaved forest. There are 36 species of national key protected plants in the reserve, such as silver fir and dove tree. The clouded leopard, black langur and white-headed langur are the first class protected animals in the state. According to the results of the survey and evaluation, combined with the local ecotourism foundation put forward the following Suggestions: the best characteristics of ornamental plants in country garden, characteristic feature edible plants in the country kitchen, healthy development of green economy, open up knowledge, white horse hill features of plant industry, increase the reserve fomous trees protect plants, the protection of both inside and outside. This study through field investigation, the early use of analytic hierarchy and private access methods, such as the white horse hill ecological nature reserve resources comprehensive evaluation on the plants, and in a lot of Zhu Wu kinds of screening and recommend a more suitable for local ecological tourism development characteristics of ornamental plants, edible plants, medicinal plants, as well as the key protection plant, to the local developing ecological tourism provides an important reference basis, also for the reasonable solution to reserve conflicts between people and provides a reference model.

Molecular cloning and potential role of DiSOC1s in flowering regulation in Davidia involucrata Baill

Davidia involucrata Baill. (dove tree) is unique Tertiary relic plant in China, also known as ‘living fossil’ and ‘giant panda’. The MADS-box family gene SOC1 is involved in the regulatory pathway that integrates flowering signals to promote flowering at the optimal time. In this study, we isolated and identified two dove tree SOC1 homologues, named DiSOC1-a and DiSOC1-b. These two sequences possess highly conserved domains MADS-box and SOC1-motif, as well as the semi-conserved region K-box. DiSOC1-a and DiSOC1-b were expressed at varying levels in all tested tissues of dove tree and shared high levels of expression in the flower buds. The expression tendencies of both genes in bract were initially upward and then downward and were highest in young bracts. Neither DiSOC1-a nor DiSOC1-b was expressed in immature leaves. Proteins encoded by DiSOC1-a and DiSOC1-b were located in the nucleus. In addition, ectopic overexpression of both genes in WT Arabidopsis promoted early flowering and the growth of the main bolt. Taken together, these results suggest that DiSOC1-a and DiSOC1-b are involved in the flowering initiation and the main bolt growth process of dove tree. Our results provide a foundation for horticultural breeding to control flowering time of dove tree.

Ectopic expression of a R2R3 MYB transcription factor of dove tree (Davidia involucrata) aggravates seed abortion in Arabidopsis thaliana.

Serious seed abortion of dove tree (Davidia involucrate Baill.) is one of the critical factors leading to the low fecundity of this species. Seed abortion is a complicated process and various factors have been verified to synergistically determine the fate of seeds. To reveal the mechanism of seed abortion in D. involucrata, we performed transcriptome analysis in normal and abortive seeds of D. involucrata. According to the transcriptome data, we noticed that most of the genes encoding a MYB transcription factor were predominantly expressed in abortive seeds. Among these, a gene named DiMYB1 was selected and its function was validated in this study. Overexpression of DiMYB1 resulted in obviously reduced viability of transgenic seeds and seedlings, and caused a significantly higher seed abortion rate. The vegetative growth of transgenic plants was hindered, resulting in an earlier flowering time. In addition, colour changes occurred in transgenic plants. Some transgenic sprouts, stems and pods appeared purple instead of green in colour. Our finding demonstrated that DiMYB1 participates in multiple plant developmental processes, especially in seed development in Arabidopsis thaliana (L.) Heynh., which indicated the similar role of this gene in D. involucrata.

Transcriptomic Responses of Dove Tree (Davidia involucrata Baill.) to Heat Stress at the Seedling Stage

The dove tree (Davidia involucrata Baill.), a tertiary relic species, is adapted to cool climates. With the progression of global warming, high-temperature stress has become the primary environmental factor restricting geographic distribution, ex situ conservation, and landscape application for D. involucrata resources. However, the detailed molecular events underlying D. involucrata responses to heat stress are poorly understood. Here, we conducted RNA-Seq-based gene expression profiling in D. involucrata seedlings during the time course of a 42 °C heat treatment (0, 1, 6, and 12 h). After de novo assembly, we obtained 138,923 unigenes, of which 69,743 were annotated in public databases. Furthermore, 19,532, 20,497 and 27,716 differentially expressed genes (DEGs) were identified after 1 h (HS1), 6 h (HS6), and 12 h (HS12) of heat treatment in comparison to 0 h (HS0), respectively. Based on a KEGG enrichment analysis, the two pathways “protein processing in endoplasmic reticulum” and “plant hormone signal transduction” are hypothesized to play vital roles during heat response in D. involucrata, and their potential interactions during heat stress are also discussed. In addition, 32 genes encoding putative heat shock transcription factors (Hsfs) were found to be associated with the response of D. involucrata to heat stress. Finally, the expression patterns of eight heat-responsive genes derived from qRT-PCR were in agreement with their transcript level alterations, as determined by a transcriptome analysis. Taken together, our transcriptomic data provide the first comprehensive transcriptional profile affected by heat stress in D. involucrata, which will facilitate further studies on the improvement of heat tolerance in this rare and endangered species.

Selection and validation of suitable reference genes for RT-qPCR analysis in dove tree (Davidia involucrata Baill.)

Fifteen candidate reference genes were selected from the dove tree genome. Their performance as internal controls for RT-qPCR analysis was assessed in bracts at different developmental stages, normal and abortive seeds, and leaves of different colors. The applicability of the candidate reference genes was validated through detection of the expression levels of three target genes normalized by different reference genes. Dove tree (Davidia) is a relic species and has some unique traits in its reproductive organs. The molecular mechanisms underlying the development of these organs have attracted increasing attention. RT-qPCR is a powerful tool for gene expression pattern detection, which is critical for studies on gene function or regulation. However, information regarding suitable reference genes, which ensures reliable RT-qPCR results, is absent in dove tree. Based on our previously obtained Davidia transcriptome data, 15 reference genes, including eight traditional and seven novel reference genes, were selected for this study. Using geNorm, NormFinder and BestKeeper software, the stability and applicability of these candidate reference genes were assessed with regard to different aspects including bract development, seed abortion and leaf color. The candidate reference genes were ranked by the software programs, and the most suitable and unsuitable genes for different situations were determined. In addition, the expression levels of three Davidia genes of interest involved in bract development, seed abortion and leaf color, respectively, were normalized with high-ranking and low-ranking reference genes. The comparison results demonstrated that the selection of “good” or “bad” reference genes led to differing conclusions.

Cloning and characterization of a CCoAOMT gene involved in rapid lignification of endocarp in dove tree (Davidia involucrata Baill.)

The long period of seed dormancy is one of the most important reasons leading to the low fertility of dove tree (Davidia involucrata Baill., Davidia hereinafter). During the fruit development process of Davidia, the endocarps will become particularly compact and hard, which was considered as a critical reason for the long seed dormancy of Davidia. However, the biological significance and regulatory mechanism of this process remain unclear. In this study, we identified a CCoAOMT gene, a key member of the lignin biosynthesis pathway, from Davidia endocarp. The gene named DiCCoAOMT1 has an ORF (open reading frame) of 744 bp and encodes a predicted protein of 239 amino acids. The expression of DiCCoAOMT1 is endocarp-specific and the expression levels increased along with the fruit development process. The encoding protein of DiCCoAOMT1 demonstrated a relatively high O-methyltransferase activity when using caffeic acid as a substrate in vitro. The tissue-specific CCoAOMT gene identified in this study might play a key role in specifically regulating the rapid lignification process in Davidia endocarp.

Agricultural Environmental Monitoring Data Classification of Fanjing Mountains: A Decision Tree Approach

Fanjing Mountains is rich in wildlife resources (such as Guizhou golden monkey, dove tree, and other rare species) and tea resources (for example, Fanjing Mountains cui feng tea, Shiqian moss tea, Vatican black tea, Jin Qiangong black tea, Eight hour black tea, vine tea and other dozens of products), where is completely unable to find traces of artificial scenery, and its main peak “mushroom stone” is a landscape. So it has great important scientific and ecological value in researching the classification of agriculture environment data in Fanjing Mountains, so as to develop various sensors about new crops of growth environment factors (e.g. soil temperature, soil moisture content, air temperature, air humidity, light intensity and carbon dioxide (CO2) concentration), as well as the biometric information of individual animals (e.g. body temperature, pulse, location information), realize the intellectualization of agriculture, establish administrative policy with the pilot of scientific research, the basis of management and protection, and the guarantee of coordination, better promote the green development of agriculture, and assure the security of resource and ecology. This article analyzes the agricultural environment monitoring data adopting the classification method of decision tree in machine learning.