Abstract:To reveal the molecular characteristics and expression pattern of C4H genes in moso bamboo (Phyllostachys edulis), six C4H gene members (PeC4H1-PeC4H6) from moso bamboo genomic database were identified by bioinformatics method. The length of gene coding region ranged from 1 506 to 1 695 bp, encoding 501-564 aa, and all of them have conserved heme binding domain, threonine binding channel motif and five characteristic substrate recognition sites, which belong to the cytochrome P450 superfamily. Phylogenetic analysis showed that the six PeC4Hs could be divided into two classes, containing 2 and 4 members, respectively. Transcriptome analysis showed that there were significant differences in the expression of PeC4Hs in 26 tissues of moso bamboo, and the expression of PeC4Hs in bamboo shoots at different heights were different by qPCR. There were a variety of cis-regulatory elements in response to stress and hormone signals in the promoter sequences of PeC4Hs. The expression of PeC4Hs was affected by drought and GA₃. Under drought, only PeC4H3/4 expression was significantly up-regulated in roots, while others were down-regulated. Treated by GA₃, the expression of PeC4H3/6 in leaves was responded rapidly and significantly up-regulated at first and then gradually decreased. The expression of PeC4H2/5 in roots was briefly down-regulated in the first hour and then significantly increased, finally recovered to the untreated level at 8 h. Therefore, PeC4Hs might play an important role in the lignification process of bamboo shoot and the response to abiotic stress.

Abstract:In order to understand the mechanism of the narcissus (Narcissus tazetta var. chinensis) floral induction, the differentially expressed metabolites and genes were screened from the outermost buds treated with exogenous ethylene by using metabolome and transcriptome sequencing techniques. The results showed that 12 differentially expressed metabolites (DEMs) were detected, including 7 up-regulated and 5 down-regulated DEMs. Among them, (±) 7-epigenJasmonic acid, dopamine and spermidine might be positively correlated with narcissus floral induction, while indole and its derivatives were negatively correlated. A total of 1 021 differentially expressed genes (DEGs) were identified in the transcriptome, including 615 up-regulated and 406 down-regulated DEGs. Forty-five differentially expressed genes related to ethylene signal transduction and flowering were identified in the DEGs. The changes of endogenous plant hormone (especially ethylene) signaling pathway in narcissus bulbs were activated firstly by exogenous ethylene, and the floral induction of narcissus via exogenous ethylene was closely related to the up-regulated expression of FPF1 and MADS15. Nine genes correlated with flowering were verified by qRT-PCR analysis and the expression profiles were consistent with the RNA-Seq results. Therefore, these DEMs and DEGs might have vital function on the narcissus floral induction, which might play an important role in the floral formation of narcissus induced exogenous ethylene.

Abstract:In order to cultivate excellent new varieties of Areca catechu, the quality identification and correlation analysis of 10 core resources were studied. The results showed that there were significant differences in quality traits among different resources. The variation coefficients of 9 traits, including equatorial diameter, transverse diameter, single fruit, arecoline, arecaidine, fructose, glucose, gallic acid and epicatechin, ranged from 7.00% to 190.13%, among which the variation coefficient of epicatechin content was the largest and that of horizontal diameter of fresh fruit was the smallest. Correlation analysis showed that the longitudinal diameter of fresh fruit was significantly positively correlated with arecoline content, while significantly negatively correlated with gallic acid content. Base on the SSR marker, 10 core resources could be divided into 3 groups, group I included S-J18-06, Z-J18-01, S-J18-08, Z-J18-05, S-J18-16, S-J18-15 and S-J18-22, group II had S-J18-19, S-J18-13, and S-J18-25 into group III. The fruit shapes of the resources in group I were all demand types of Hainan processing enterprises. The germplasm resource (group III) S-J18-25 of A. catechu contains high epicatechin content and specific alkaloids, which could be exploited and utilized in breeding.

Abstract:To understand the endangered reasons of Dipteris chinensis, a rare and endangered plant, the effects of temperature and humidity on spore germination was studied. The results showed that the spore germination ability was strong, with Vittaria-type germination mode and Marattia-type gametophyte germination. The spore propagation of D. chinensis was not affected by temperature, while significantly influenced by humidity. The spores germinated normally in humid condition, forming heart-type gametophytes, and producing young sporophytes successfully. However, spores could not germinate under drought condition, gametophytes were inclined to irregularly development and folds increased. Therefore, the obstacles in spore reproduction of D. chinensis under unsuitable environment might be one of the reasons leading to the decline of wild population, so that in situ and ex situ conservation of these rare and endangered plants should pay attention to creating moist habitats.

Abstract:Tea cultivar ‘Huangshanbaicha No. 1’ (HSBC#1) was bred from natural albino mutants of tea plants. The green tea processed from HSBC#1 possess umami, mellow taste and fresh odor. For investigating the metabolite profile of green tea produced from three albino stages (early, middle, and late) of HSBC#1, the main components in tea, such as volatile compounds, catechins, caffeine, and free amino acids, were analyzed. The green teas produced from different stages of HSBC#1 showed the different odor and taste via sensory evaluation. A total of twenty-nine volatiles was identified and quantified. The principal component analysis indicated that the top five differential volatiles were geraniol, (Z)-hexanoic acid, 3-hexenyl ester, linalool, (Z)-3-hexen-1-ol, and (Z)-butanoic acid, 3-hexenyl ester, approximately contributing to the differences in aroma among green teas. Catechins were lower concentrated in early-stage green tea, but their concentrations increased significantly in late-stage green tea. The amount of caffeine had no difference in three types of green tea. The total content of free amino acids in early-stage green tea accounted for about 4% of dry weight, while that in late-stage green tea only for 1.3% of dry weight. Therefore, the differences in metabolites among tender shoots of HSBC#1 at different albino stages lead to the difference in the flavor of green tea products.

Abstract:In order to promote the breeding process of Chinese fir (Cunninghamia lanceolata), growth and cone production traits of parent clones at 3-year-old in the third generation breeding gardens of Chinese fir in Longshan Forest Farm of Lechang City and Xiaokeng Forest Farm of Qujiang District of Shaoguan City in Guangdong Province were studied. The results showed that all of the growth traits, such as height, diameter at breast height (DBH), individual volume and canopy, varied significantly (P<0.01) among clones in the same breeding garden with phenotypic and genetic variation coefficients ranged from 12.8% to 73.5% and 6.5% to 59.2%, respectively. Furthermore, all of growth traits had high repeatability (≥ 0.70), which was beneficial for parent re-selection. The best linear unbiased prediction method (BLUP) was used to estimate the breeding values of each parent clone regarding different growth traits and resulted in a ranking. When selection was made for growth (the breeding values of growth traits were all in the top 50%) and cone production traits, 22 and 30 elite parents were identified from Longshan Breeding Garden and Xiaokeng Breeding Garden respectively, with a common list harboring the clones of cx836, cx837, cx840, cx845, cx851, cx856, cx859 and cx877.

Abstract:In order to excavate the waterlogging resistant germplasm resources of Hibiscus mutabilis, the morphological, physiological and biochemical indexes of 13 cultivars were studied after 15 days of flooding, and build the evaluation system of waterlogging resistance. The results showed that the variation trend and range of morphological and physiological indexes were different among cultivars, and the correlation of some indexes was significant (P<0.05). The 14 indexes were attributed to morphological growth index, adventitious root morphological index, membrane lipid peroxidation index, root biomass index, antioxidant index and osmotic regulation index according to contribution rate. Cluster analysis conducted according to comprehensive waterlogging resistance evaluation value (D) showed that 13 H. mutabilis varieties could be divided into four waterlogging tolerance types, including very strong (3 varieties), stronger (5 varieties), medium (3 varieties) and none waterlogging tolerance (2 varieties). Therefore, the plant height, adventitious root number, adventitious root length could be used as rapid and simple indexes to identify the comprehensive waterlogging tolerance at seedling stage in H. mutabilis.

Abstract:In order to accelerate the growth of Parashorea chinensis seedlings, the Bacillus agents and dosage were selected. The seedlings at 1.5-year old were treated with different concentration Bacillus agents, including B. mucilaginosus, B. laterosporus, and B. megaterium, respectively. The results showed that the growth and photosynthetic indexes of seedlings were improved by three Bacillus agents. Compared to CK (irrigated only with clean water), the height and diameter increment of P. chinensis seedlings increased by 30.2%-57.2% and 5.3%-49.7%, the root activity increased by 74.5%-227.4%, while the net photosynthetic rate increased by 15.3%-227.6%. The seedling height, ground diameter, biomass, root surface area, root average diameter, leaf area and chlorophyll content were the highest under the treatment of 6.0×10⁹cfu/g B. megaterium, as well as the net photosynthetic rate, ФPSⅡ and qP, which were consistent with the results of seedling quality index and membership function method. Therefore, Bacillus megaterium at 6.0×10⁹ cfu/g was the most beneficial microbial agent to improve the growth and development of P. chinensis.

Abstract:In order to understand the migration and absorption characteristics of cadmium, the differences in absorption, migration and distribution of cadmium were studied in Sphagneticola calendulacea (indigenous congener), S. trilobata (alien invasive species) and their hybrid treated with Hoagland solution containing 200 μmol/L CdCl₂. The results showed that the cadmium concentrations in stems and leaves of three species gradually increased with the time extension of cadmium treatment, and the cadmium concentrations in leaves gradually matched that in stems, while that in roots of three species was always the highest. For the whole plant, cadmium concentration of the hybrid was also the highest under stress. After recovery growth, the cadmium concentrations in roots of hybrid, S. calendulacea, and S. trilobata declined by 50.4%, 35.8%, and 33.7%, respectively. Distribution pattern of cadmium in leaves of three species had not significant change treated with/without CdCl₂. The hybrid tended to accumulate cadmium in young and mature leaves. The cadmium concentrations gradually decreased from vein, internal vein and leaf edge of three species, which in internal vein of S. trilobata was the highest (2 766.3 μg/kg). Therefore, the hybrid displayed stronger ability to absorb, transport and transfer cadmium than its parents, suggesting that it had greater potential in phytoremediation in the future.

Abstract:In order to understand the relationship between community structure with species diversity of artificial mixed forest, the community structure of Phoebe bournei-Cinnamomum camphora mixed plantation in Longyandong Forest Farm in Guangzhou was analyzed. The results showed that there were 128 species 9 563 plants in 0.37 hm² quadrat, belonging to 57 families and 99 genera, in which there were 35 tree, 61 shrub, and 98 herb species. In tree layer, the species with importance value at top 5 were Triadica cochinchinensis (33.86%), Phoebe bournei (17.24%), Triadica cochinchinensis (12.96%), Melicope pteleifolia (7.92%), and Litsea pungens (3.70%), the shrub layer was dominated by Rubiaceae, and did the herb layer by Poaceae. The Shannon-Wiener indexes of tree, shrub and herb layers were 1.230, 1.708, and 1.754, respectively, and the Simpson indexes were 0.635, 0.680, and 0.707, indicating that artificial mixed forest was rich in herbaceous species. The non-metric multidimensional scale (NMDS) analysis showed that the similarity of species composition was not consistent in different plots, and some plots contained occasional species. The diameter class structure of the community showed an inverted "J" type, of which 11.64% were seedlings, and saplings, small trees, strong trees and large trees account for 6.08%, 55.34%, 25.28%, and 0.70%, respectively. Therefore, it was suggested that the Phoebe bournei-Cinnamomum camphora mixed plantation was still in the early successional stage.

Abstract:Twelve species of Fissidens are reported for Wuyanling National Nature Reserve, Zhejiang Province, China. Fissidens involutus Wilson ex Mitt. var. jejuensis Y.-J. Yoon, B.C. Tan & B.-Y. Sun, a new variety previously known only from Japan and South Korea, is reported here for the first time from China. This species is characterized by the bases of dorsal leaves are distinctly decurrent, and cells of vaginant lamina have single indistinctly papilla at each corner. Detailed description and illustrations of F. involutus var. jejuensis are provided. In addition, two species, viz. F. anomalus and F. serratus are new provincial records for Zhejiang Province. In Wuyanling, a humped distribution is observed of the Fissidens species diversity with the elevation. Compared with other nature reserves in southeastern region of China, the number of species of Fissidens in Wuyanling is the second only to Yachang Nature Reserve (Guangxi). Furthermore, species diversity of Fissidens does not increase as the latitude decreases in this region. Hence, it is recommended to carry out further investigation and study on the diversity of Fissidens in southeastern region of China.

Abstract:To investigate the changes of leaf epidermal morphology in albino mutants of woody plants, the epidermis cells and stomatal apparatus on leaves of albino mutant (AAS) and normal (CK) Artocarpus hetero-phyllus seedlings were observed under scanning electron microscopy. The phylogenetic tree was constructed based on MAP65 family proteins, and the expression of MAP65 was analyzed. The results showed that the size and morphology of epidermal cells and stomatal apparatus of AAS were changed greatly. Compared with CK, epidermal cells of AAS had smaller perimeter and area, higher density, less lobe number, shorter lobe length and smaller stomatal apparatus. The number of small cells and abnormal stomatal apparatus in lower epidermis increased significantly in AAS. Most genes of MAP65 family members were down regulated in AAS. Therefore, it was speculated that the occurrence of AAS might be related to the expression of MAP65 gene.

Abstract:Two suspicious species of Asteraceae tribe Vernonieae were discovered in Hainan Province, China. Detailed morphological investigation suggests that they are Koyamasia curtisii and Struchium sparganophorum. Molecular data based on nrDNA ITS sequence provide further support of the status of K. curtisii. These two species represented two genera that have not been reported from China. Therefore, they are two newly recorded genera for China.

Abstract:Iris junzifengensis S. P. Chen, X. Y. Chen & L. Ma, a new species of Iridaceae from Mingxi County, Fujian Province of East China, is described and illustrated here. The new species is similar to I. japonica Thunb. and I. formosana Ohwi, but is distinguished from the former by the broad leaf blades with distinct veins and rough surface, terminal sparse racemose cyme with 2-6 branches, bigger flowers that are 5.0-7.0 cm in diam, perianth with undulate margin and retuse apex, and triangular cylindrical capsule, and from the latter by smaller flowers, perianth with undulate margin and retuse apex, and triangular cylindrical capsule. The comparison of morphological characteristics and molecular phylogenetic analysis both support the establishment of the new species.

Abstract:Suanzhi Wood, the largest rare and costly wood group of rosewood, containing 13 species of genus Dalbergia in Leguminosae family. To facilitate accurate identification of the Suanzhi Wood, the morphological descriptions of these Suanzhi Wood species based on a taxonomic review were provided.

Abstract:Dense fern understory (DFU) is widespread in forests, especially in disturbed forests, which has a strong filtering effect on tree species regeneration and can change the diversity of understory and affect the structure, function and dynamics of forest community. Thus, ecological studies on DFU are vital to reveal the distribution patterns of species and the community assembly rules. Combined with the latest studies at worldwide, the characteristics of DFU was summarized, and the main reason for the formation of DFU was explained by mechanism. The pathways of DFU effect on the forest regeneration through resource competition, allelopathy animal feeding strategies and mechanical interference were described. The potential influence of DFU on the forest succession was also discussed. Finally, several shortcomings of current studies of DFU were identified.