Abstract:In order to understand the genetic diversity of Jacaranda mimosifolia germplasm resources, 168 germplasms of Jacaranda mimosifolia were restriction-site associated DNA sequencing (RAD-seq), and then the phylogenetic tree was constructed, principal component (PCA), population structure and genetic diversity were analyzed. The results showed that the mean alignment rates to the reference genomes were 81.02% with an average sequencing depth of 23.18×. After cleaned and filtered, a total of 45 552 SNPs were obtained. All tested germplasms could be clustered into two groups, those from Sichuan-Chongqing region were in one group, and the rest were in another group. Jacaranda mimosifolia has a high genetic diversity at the SNP level. Among them, nucleotide diversity (π) and expected heterozygosity (He) in YNKM population is the largest, showing the highest genetic diversity. Therefore, Jacaranda mimosifolia from Sichuan-Chongqing region showed relatively close genetic relationship, suggesting that they might from the same ancestor, and those from other regions might be randomly introduced and cultivated.

Abstract:To reveal the effects of shoot pinching on the growth, sucrose and starch metabolism in ‘Kyoho’ grape (Vitis vinifera×V. labrusca) and its mechanism, the phenotype of leaves and stems, accumulation characteristics of soluble solids, sucrose and starch in fruits, and expression of genes related to sucrose and starch metabolism were studied by different ways of shoot pinching. The results showed that shoot pinching inhibited leaf growth and stem enlargement of ‘Kyoho’, but promoted the rapid growth of inflorescence in early stage, and increasing fruit weight, ear weight, plant yield and soluble solid content. The contents of sucrose in leaves, sucrose and starch in stems increased in late stage under 2-leaf pinching, and the expression of SPS, NI and CWI in sucrose metabolism enhanced, while that of AMY in starch metabolism inhibited. Therefore, it was suggested that 2-leaf pinching could regulate the expression of SPS, NI, CWI and AMY genes, and promoted sucrose synthesis and starch accumulation, laying a nutritional foundation for fruit ripening, germination and flowering.

Abstract:Tiger nut (Cyperus esculentus) originated from the Mediterranean Coast in North Africa. It is a special oil crop that stores oil in tuber tissues. In order to popularize the cultivation of tiger nut, it is urgent to study the basic biological characteristics of cultivated tiger nut lines in China. Therefore, the germplasm lines from the main planting areas of tiger nut in China were collected. After field planting, some characters of tuber and plant and their correlation among lines were compared and analyzed. According to tuber size and tuber shape, these cultivated tiger nut lines could be divided into three basic types, namely long tuber, big tuber and round tuber. Under the field planting conditions, the flowering rates of each lines ware very few, and there was no significant difference in the number of tuber buds and tuber rings among these lines. However, these three types of tiger nut have great differences in oil content, leaf and plant morphology, and tillering characters. The leaf length-width ratio was significantly positively correlated with the tuber height-width ratio, but the correlation between leaf morphology and tuber oil content was not significant. These would provide important reference for field planting and variety breeding of tiger nuts.

Abstract:In order to investigate the effects of different membrane separation processes on product quality, biochemical components and antioxidant activity in vitro, the water extract of Oolong tea was separated by ceramic membrane (500 nm) and ultrafiltration membrane (20, 10, 5, 3.5 kD), and tea powder was prepared by spray drying. The quality of tea powder prepared by different membrane separation processes was evaluated through sensory quality and physical properties, and the main biochemical components of tea powder were analyzed and compared. Meanwhile, the antioxidant activity of tea powder in vitro was evaluated by DPPH radical scavenging capacity, the ferric ion reducing antioxidant power (FRAP), hydroxyl radical scavenging capacity and anti- superoxide anion activity. The results showed that the sensory quality and antioxidant activity of ceramic membrane were the highest. The 500 nm ceramic membrane can effectively separate and enrich tea polyphenols (TPs), free amino acids (FAAs), caffeine (CAF), soluble sugar (SPS) and other substances, but also achieve the effect of impurity removal. The water extract of Oolong tea separated by ceramic membrane and then separated by ultrafiltration membrane, TPs, CAF, SPS, catechin components have no separation and enrichment effect. Ultra- filtration membranes with molecular weight less than 10 kDa can effectively separate and enrich free amino acids. The 500 nm ceramic membrane interception solution had the highest SPS content, but the worst sensory quality and the lowest antioxidant activity. Therefore, considering the three factors of quality, efficiency and energy saving, the comprehensive quality of tea powder prepared by 500 nm ceramic membrane through liquid is the best.

Abstract:In order to understand the changes of polysaccharide content in Gentiana apiata before and after flowering, the extraction process of polysaccharides was optimized by response surface method, and the antioxidant activities of polysaccharides were determined. The results showed that the content of polysaccharide in G. apiata after flowering was higher than that before flowering. The optimal extraction process were extraction 3 h, the solid-liquid ratio of 1∶16, the alcohol precipitation ratio of 1∶10, and the centrifugal speed at 1 537×g. Under optimal extraction conditions, the extraction rate of polysaccharide was 5.13%, close to the predicted value of 5.42%. Polysaccharides had certain antioxidant capacity to DPPH and ABTS, which was higher than that of Vitamin C and butylated hydroxytoluene. Therefore, it was suggested that G. apiatacan also could be used as antioxidant in food and health care products except for medicine.

Abstract:In order to clarify the pharmacodynamic basis of water extract from Vicia faba flowers, the chemical constituents were analyzed and identified by ultra performance liquid chromatography electrospray ion source quadrupole time of flight mass spectrometry (UPLC-ESI-QTOF-MS), and the antioxidant activity was determined. The results showed that 178 components were identified from the water extract, and the relative contents of 107 components were more than 0.01%. The components with higher relative content included scutellarein 7-neohesperidoside, indoxyl glucuronide, spirolide E, rutin, propylene glycol alginate, kaempferol 3-α-d- galactoside, xanthurenic acid, and so on. The main components of flower water extract were flavonoids and alkaloids, with 16 and 19 kinds, and their relative contents were 36.53% and 34.33%, respectively. The IC₅₀ of flower water extract for scavenging DPPH and ABTS⁺ free radical was 26.5 and 25.0 µg/mL, respectively. Therefore, flavonoids and alkaloids were the main substance basis of V. faba flower, and the water extract had strong antioxidant activity, indicating V. faba flowers had high application value.

Abstract:In order to understand the correlation between characters of single nucleotide polymorphism (SNP) of internal transcribed spacer (ITS) sequences and composition of steroidal saponins of Paris polyphylla var. yunnanensis, the effect of SNP on the quality stability of medicinal materials, the ITS sequences of 37 samples were compared by MegAlign, and then classified according to SNP loci. In addition, 7 steroidal saponins (polyphyllin Ⅰ, Ⅱ, Ⅴ, Ⅵ, Ⅶ, H, dioscin) in samples were determined by HPLC-DAD. The steroidal saponin composition characteristics of each genotype were statistical analysis by SPSS 25.0 & SIMCA-P 15.0. The results showed that there were 40 double-allelic polymorphic sites in ITS sequences of P. polyphylla var. yunnanensis, including 32 base conversion sites and 8 base inversion sites. According to SNP characteristics, 37 samples were divided into two genotypes: YN-I and YN-II. Six kinds of steroidal saponins (polyphyllin Ⅰ, Ⅱ, Ⅵ, Ⅶ, H, dioscin) were widely distributed in samples, while polyphyllin Ⅴ was relatively rare. The mean total content of pharmacopoeia index components in YN-I and YN-II were 1.070% and 0.93%, which the sample pass rate were 68.42% and 77.78%, respectively. The mean total content of 7 steroidal saponins were 1.65% and 1.32%, respectively. ANOVA analysis showed that there was significant differentiation of steroidal saponins profile between two genotypes, while there was no significant difference in the index components of pharmacopoeia, so the medicinal value of two genotypes should be equivalent. Cluster analysis (CA) and principal component analysis (PCA) showed the dispersion of YN-I was higher than that of YN-II, indicating the quality of medicinal materials of YN-II was more stable and the individual differences in steroidal saponins synthesis and accumulation in YN-II was smaller than YN-I. Therefore, the SNP characteristics of YN-II were of great significance for the screen of molecular genetic markers in the breeding of Paris polyphylla var. yunnanensis.

Abstract:In order to clarify the pigment composition and color mechanism of petals of Melastoma, the anthocyanins in 5 species were determined, the structure and distribution of petal epidermal cells were observed, and the influence of pH value, soluble sugar and soluble protein content on flower color was analyzed. The results showed that the petals of Melastoma had not chlorophyll and carotenoid, violet color mainly contained anthocyanin and flavonoids, and flavonoids in white color. The anthocyanins distributed in upper and lower epidermis of M. candidum and M. sanguinrum petals, and aslo in palisade tissue of M. malabathiricum, but the petals of M. candidum f. albiflorum and M. malabathricum var. alba had no pigment accumulation. The cells in upper epidermis of violet Melastoma show conical protrusions, which in white Melastoma show irregular flat shape, and those in lower epidermis of both colors show irregular flat shape. The brightness (L^*) of flower color decreased with the deepening of petal color, which was negatively correlated with the redness (a^*) and positively with the blueness (b^*). The anthocyanin content had significantly negative correlation with L^* and b^*, and as well as pH and a^*. Therefore, anthocyanin was the main determinant of flower color in genus Melastoma, anthocyanin content, pigment distribution and shape of upper epidermis cells were the main factors that cause color diversity.

Abstract:In order to understand the main factors of soil affecting wetland plant diversity, 18 sample plots were selected from 9 wetland types in Guangfo area. The wetland community species composition, plant diversity and soil factors were studied through field work and laboratory experiment. Furthermore, the correlations among community distribution, plant diversity and soil factors were analyzed by variance, canonical redundancy analysis (RDA) and canonical correspondence analysis (CCA). The results showed that there were 312 wetland species, belonging to 90 families and 198 genera, with Gramineae, Cyperaceae and Compositae as the dominant families. In addition, herbs are the most abundant in wetland plants, accounting for 79.17%. The principal component analysis showed that the level of soil nutrients in offshore and coastal wetlands was high. Moreover, the RDA analysis showed that soil factors with a great impact on plant diversity were soil organic matter, total nitrogen, total phosphorus, total potassium and alkali hydrolyzable nitrogen. From CCA, the main influencing factors of soil environmental factors on wetland herb community distribution are pH, available potassiumand available phosphorus. In conclusion, wetland ecosystem was more complex and fragile than terrestrial ecosystem, and the relationship between plant community and soil environmental factors was also more complex. The species distribution pattern, community diversity, community structure, soil conditions and their relationship of wetland vegetation are more obviously affected by the human disturbance.

Abstract:Leaf functional traits are closely related to plant growth strategies and resource utilization ability. In order to explore the adaptation strategies of psammophytes to environment in Hainan Island, the leaf functional traits of Vitex trifolia, Clerodendrum inerme, Lantana camara, Eupatorium odoratum, Stachytarpheta jamaicensis and Ipomoea pes-caprae and their relationships with soil chemical properties were analyzed. The results showed that the leaf functional traits of tropical psammophytes were different among species, which were affected not only by species but also by soil factors. The specific leaf area of species were in the order of herb>shrub>vine. The N/P ratio of leaves ranged from 7.78 to 10.85, suggesting that the growth of tropical psammophytes was restricted by soil N. The variation coefficient of Na content in leaves was the highest, ranging from 18.46% to 76.36%, indicating that species had a great difference in the absorption of Na⁺, which would affect its natural distribution in coastal sandy land. The specific leaf area, leaf dry matter content had negative correlations with K and Na contents in leaves, as well as N/P ratio of leaves with Na content in soil, Na content in leaves with soil organic carbon, total P and total K, implying that sandy plants adapted to salt stress through specific leaf area change. Therefore, applying soil fertilizer would be an important measure for rapid restoration of coastal sandy vegetation, and the Na⁺ content in leaves could be used as the main index for salt-tolerance screening of sandy plants in tropical coast.

Abstract:In order to understand the growth characteristics and survival status of the endangered Camellia luteoflora, an inventory of C. luteoflora resources was carried out in Chishui Alsophila National Nature Reserve, Guizhou Province. The height and ground diameter of each plant were investigated by sampling method, and the population number and structural characteristics were statistically analyzed. The population was divided into specific age groups with 0.5 cm diameter interval and classified into 5 diameter class from I to XV. A static life table was drawn to analyze the survival potential and development trend of the population. The results showed that a total of 545 individuals of C. luteoflora were found in the survey, the number varied greatly in different niches, ranging from 24 to 120. The number of individuals with ground diameter less than 0.5 cm and height less than 0.5 m were very few, and the maximum population was maintained with average ground diameter of 0.5- 2 cm. The mortality and extinction rates of I-II age class (0-1.0 cm) population increased sharply, while the life expectancy decreased sharply. The mortality and life expectancy of II-XV age class (≥0.5 cm) population tended to be flat, while the extinction rates fluctuated greatly but generally tended to be flat. The population structure and survival curve showed that the population was close to Deevey-I type, belonging to the declining population. Therefore, the seedling number of C. luteoflora population was seriously insufficient, the population self-renewal was difficult, the existing population interference pressure was large, showing obvious population decline trend, it was urgented to strengthen the population conservation.

Abstract:In order to realize the status and ornamental value of wild germplasm resource of Rhodoleia (Hamamelidaceae) in China, a detailed field survey and recourse collection of 6 species of Rhodoleia was conducted. Based on cultivation experiments, a comprehensive evaluation index system was established by linear weighted synthesis method, and the potential in landscape application of Rhodoleia species were evaluated. The result showed that the comprehensive value of R. championii, R. stenopetala, R. parvipetala was high (Grade I with score>2.0), that of R. henryi was medium (Grade II with score 1.5-2.0), and that of R. forrestii and R. macrocarpa was low (Grade III with score<1.5). As excellent local arbors with gorgeous flower, R. championii, R. stenopetala, and R. parvipetala bear very high application potential in ornamental value, cultivation adaptability and novelty of development, which is worth further investigation and utilization.

Abstract:In order to improve the morphological description of Firmiana danxiaensis, the macroscopic morphological characteristics of plants in four distribution points on Danxia and Karst landforms were compared. Specimens were collected at the three known distribution points (Danxia Mountain, Nanxiong, and Yingde) and the newly discovered distribution point (Shixing) during the flowering and fruiting periods. The results showed that there were obvious differences from the original description in petiole, leaf, inflorescence, stamens, follicle, calyx, etc. The original description lacked aborted stamens, aborted ovary, color changes in calyx, pericarp and seed coat during development. Therefore, the morphological description of F. danxiaensis was revised or supplemented, and pictures were also provided.

Abstract:WOX (WUSCHEL-related homeobox) transcription factors (TFs) are closely associated with plant development, including embryogenesis, somatic embryogenesis, flower and root development, the initiation and maintenance of callus, and stem cell maintenance in plants. Increasing studies demonstrated that WOX TFs play a crucial role in plant development. Studied on the regulatory mechanisms of WOX in plant development provide a breakthrough in promoting plant development and constructing excellent plant phenotypes. The regulation of WOX TFs in plant development was reviewed, and the developmental processes by integrating WOX and epigenetic regulation were discussed, which aimed at providing inspiration for the mechanism of WOX TFs in regulating plant development.

Abstract:Cyatheaceae is an ancient relict plant. The existing natural communities of Alsophila spinulosa are very rare. Cyatheaceae distributes in high temperature, humidity and light spots, often in patches at the edges of evergreen broad-leaved forests. Currently, the main problems facing the conservation of A. spinulosa are ecological tourism, deforestation, environmental pollution, illegal picking and mining of medicinal materials, etc., which lead to the disturbance and fragmentation of habitat and the number decrease of A. spinulosa. The conservation methods of A. spinulosa mainly include in situ conservation and ex situ conservation, and the application of molecular biology technology in breeding is increasing gradually. The distribution and diversity of A. spinulosa are restricted by biological and abiotic factors, and the growth and distribution are greatly affected by biological factors, especially the interspecific relationship. The conservation of A. spinulosa from the perspective of interspecific relationship may be an effective way in the new era. The interspecific relationships between Cyatheaceae plants with microbial, other plants and animals were discussed, as well as the factors causing the extinction of A. spinulosa and the related conservation strategies and effects in recent years, which would provid a theoretical basis for the effective utilization and protection of A. spinulosa.

Abstract: