Abstract:HSSP is a 10 kD Zein gene modified with soybean codon. In the previous study, a single copy of transgenic soybean GSDH5 was screened from the genetically modified soybeans. In this study, the left boundary flanking sequence of the TDNA insertion site of the transformation soybean GSDH5 was obtained by chromosome walking method, and the left boundary flanking sequence was analyzed, the specific primers were designed, and the specific detection method of transformation soybean GSDH5 was established. Realtime PCR was used to detect the expression of foreign genes in different tissue parts of transgenic soybean (root, stem, leaf, flower and seed), RTPCR and Western blot were used to detect the genetic stability of the target gene at the transcriptional and translation levels. The contents of crude protein, sulfurcontaining amino acids and main agronomic characters in the transgenic soybean GSDH5 were determined and analyzed, which laid a foundation for cultivating new varieties of transgenic soybeans with high sulfur amino acids. The results showed that: (1) molecular identification showed that the exogenous gene HSSP and the screening marker gene Bar were successfully integrated into the soybean ‘Dongnong 50’ genome, and were integrated into the soybean genome in the form of single copy. (2) HSSP gene was successfully inserted into 52 873 883 bp of noncoding region of soybean genome 1. (3) HSSP gene was specifically expressed in the seeds of transgenic soybean GSDH5, and could be stably inherited and expressed in T₂-T₄ transgenic soybeans. (4) The range of crude protein content of ‘Dongnong 50’ was 41.53%-43.32%, and that of GSDH5 was 40.18%-43.03%. There was no significant difference between the two. Sulfur amino acids in GSDH5 seeds accounted for 1.35% of seed dry samples and 3.14% of seed protein, which increased significantly by 11% and 16%, respectively. (5) There were no significant differences between transgenic soybean GSDH5 plant and acceptor variety ‘Dongnong 50’ in pod number per plant, 100seed weight, plant height, pod forming habit, flower color, leaf shape and other aspects, which proved that the insertion of HSSP gene had no adverse effects on the growth and development of soybean plant. It is suggested that the transgenic soybean GSDH5 material has the potential to cultivate new soybean varieties with high sulfur amino acid content.

Abstract:Cucurbita ficifolia Bouche. is a unique cucurbits germplasm resource in Yunnan Province with highly Fusarium wiltresistance genetic trait. To explore the function of NBSLRR type genes from C. ficifolia, in this study, we isolated the NBS type gene of CfRFN2 (GenBank ID：MK618462). We obtained a full length 4 303 bp by divided three fragment cloning using RTPCR method from leaves of C. ficifolia. The CfRFN2 gene was annotated as a homologous gene of transcriptionoid X1 of Arabidopsis diseaseresistant protein At4g27190, with complete coding frame length of 4 092 bp and encoding 1 363 amino acids, and its deduced protein contained one NBARC conserved domain and two LRR domains. The CfRFN2 gene belongs to a hydrophilic protein containing the signal peptide. The results of nucleotide similarity analysis indicated that the identity of CfRFN2 gene varied from 87% to 98% when compared with the other disease resistance genes in Cucurbitaceae crops. Phylogenetic analysis results showed that CfRFN2 protein and other NBS type protein from cucurbits crops were clusterd into one branch, indicating it had closer genetic relation among cucurbits crops than with other species NBS protein. Moreover, CfRFN2 had the closest genetic relation with RPS2 of Cucurbita pepo and Cucurbita moschata, Cucurbita maxima RPS2like protein, followed by Cucurbita sativus At4g27190 and Momordica charartia At4g27220, while relatively quite far from Cucurbita melo At4g27190. The tissue specific expression results indicated that the CfRFN2 gene was highly expressed in leaves than that in stems, and had low expression level in fruits and roots. Furthermore, based on the tobacco rattle virus vector system, we also constructed VIGS silencing vector pTRV2CfRFN2, constantly the seedlings of C. ficifolia were infected by Agrobacterium tumefaciens carrying silencing vector and inoculated with Fusarium oxysporum after 4 weeks infection (wild type plants inoculation pathogeny simultaneously). The qRTPCR analysis showed that, compared to the wild type plant, the expression of CfRFN2 gene in silencing plants decreased by 34.75% and 98.27%, respectively after 2 and 4 days inoculation. Moreover, the average disease index of silencing plants was 1.32 times that of wild type plants. This preliminarily results suggested that CfRFN2 gene in C. ficifolia had the function of resistance to Fusarium wilt. The cloning and VIGS confirmation of NBS type gene CfRFN2 would be the basis for digging more disease resistant genes in C. ficifolia, and thus provide a new clue for carrying out molecular breeding and exploring the disease resistant mechanism in cucurbits crops.

Abstract:MYB transcription factors are widely involved in plant growth and development, and also play an important role in regulating lignin synthesis. In this study, in order to explore the role of MYB transcription factor in maize development, the differentially expressed MYB transcription factor genes were screened and analyzed based on the transcriptome sequencing data of maize stems，and the ZmMYB308 gene was cloned by RTPCR method. The results showed that: (1) a total of 14 differentially expressed MYB transcription factor genes were detected in different periods, among which 10 were downregulated and 4 were upregulated. (2) ZmMYB308 contains a 747 bp open reading frame, which encodes a 248 amino acids polypeptide with a protein molecular weight of about 27.01 kD and a theoretical isoelectric point of 9.17. Blast results showed that ZmMYB308 was closely related to SiMYB308 of foxtail millet with 94% similarity. (3) The results of real time quantitative PCR analysis showed that ZmMYB308 was significantly differentially expressed in different development periods and tissues. The expression of the ZmMYB308 first increased gradually and then decreased with the development of maize stem, and reached the peak at the silking stage. Meanwhile, ZmMYB308 was highly expressed in maize stems and roots which had lignin content. The results indicated that ZmMYB308 might play an important role in the regulation of stem growth and development. This work lays the foundation for further exploring the molecular regulatory mechanism of lignin synthesis in maize.

Abstract:Methylbinding domain proteins (MBDs) are a group of transacting factors that bind to methylated DNA sites, and play important roles during the developmental regulation in plants. In this study, we used ‘Chinese Spring’ as materials, and bioinformatic analyses were performed to identify the TaMBD genes in the wheat genome, including composition, sequence characteristics, chromosomal location and expression patterns, Additionally, the spatiotemporal expression patterns of TaMBD6 and TaMBD9 genes were studied by using qRTPCR technology. The results showed that: (1) 16 TaMBD members (44 gene loci) were included in the wheat genome, and they were distributed on the 1st, 2nd, 5th, 6th and 7th chromosome groups, respectively. Cluster analysis indicated that TaMBDs were sorted into six subclasses Ⅰ, Ⅱ, Ⅲ, Ⅴ, Ⅶ and Ⅷ of eight MBD subclasses in plants. Additionally, 5 conserved binding sites, specific to methylated DNA regions, were found in the TaMBD members of the subclass Ⅱ, Ⅲ and Ⅷ. Gene structure analysis showed that the number of introns is varied at the range of 1 to 10 in TaMBD genes, and the light and hormoneresponsive elements were commonly found in the region of TaMBD promoters. The distribution characteristics of genomic structure and regulatory elements were highly similar among TaMBD members in the same subclass. (2) Gene expression profile analysis of RNASeq data showed that most members of TaMBD gene family were highly expressed in grain and spike tissues at the time point of earlier development stages, and some members were obviously responding to both of drought and heat stresses. (3) The qRTPCR results showed that the 3 homologous genes of TaMBD6 and TaMBD9 were differentially expressed in different tissues, but they were all expressed at the highest level in young spike tissues. The results indicated that the MBD genes might play important regulatory roles during the process of developmental regulation and abiotic stress responding in wheat.

Abstract:To explore the resistance function of chitinase to gray mold disease in Lilium spp., we cloned a chitinase gene LoChi2 (GenBank accession number: MW310626) by reverse transcription PCR from the highly resistant cultivar L. oriental hybrid ‘Sorbonne’ after Botrytis elliptica infection for 12 h. Structural and functional characteristics of the protein encoded by LoChi2 gene were predicted through bioinformatic methods, and the expression patterns of this gene in response to B. elliptica infection and JA/SA treatment were analyzed by qRTPCR. The results shows: (1) the open reading frame of LoChi2 is 915 bp long and encodes 304 amino acids with a predicted molecular weight of 32.52 kD and a calculated isoelectric point of 4.16. (2) Protein structural and phylogenetic analyses revealed that LoChi2 is a member of Class Ⅲ from glycoside hydrolase 18 family. As a secretory protein with hydrophobicity, LoChi2 is located outside the cell. It includes a conserved GH18 narbonin catalytic domain, a transmembrane domain, as well as signal peptide, glycosylation, and phosphorylation sites. Multiple sequence alignment of the deduced amino acid sequence of LoChi2 displayed high similarity with the sequences of several Chi2 genes from L. longiflorum, Ananas comosus, and Prunus mume. (3) qRTPCR analysis showed that the expression levels of LoChi2 were positively correlated with gray mold disease resistance among different cultivars. More transcripts of LoChi2 accumulated in the highly resistant cultivar ‘Sorbonne’ than in the moderately susceptible L. × formolongi ‘Raizan 3’ and highly susceptible L. asiatic hybrid ‘Tresor’ after infected with B. elliptica; the expression of LoChi2 was induced by exogenous salicylic acid and jasmonic acid treatments. Overall, our findings indicate that LoChi2 is a critical gene involved in lily defense against gray mold disease, and this gene may play an important role in the JA and SA mediated defense signaling pathways. We thus speculate that it will become a new candidate gene with broad application prospects in the transgenic breeding of lily resistance to this disease.

Abstract:The pollen and leaf epidermis morphology of seven species of Physospermopsis in Apiaceae were observed by scanning electron microscope, the pollen morphology of three species of Physospermopsis was first reported, and the leaf epidermis micromorphology of seven species was first reported, which provided reference materials for the research on the interspecific relationship and phylogeny of Physospermopsis. The results indicated that: (1) the pollens of seven species of Physospermopsis are rhombic, ellipsoidal, and subrectangular, the polar shapes include triangular, triangularrounded and blunt triangular. The ratio of pollen polar axis to equatorial axis P/E is 1.22-2.07, and the size index is 16.59-19.26. The position of the aperture is the goniotreme, the equatorial sculptures are all cerebroid. (2) The contours of leaf epidermal cells of seven species of Physospermopsis are not clear, only the leaf epidermal cells of P. muliensis are regular polygonal, and the ornamentation of cuticle has irregular stripes. The stoma of P. delavayi, P. shaniana, P. rubrinervis and P. obtusiuscula are only distributed on the abaxial plane. The shape of the stoma is elliptical or ovate, the length of the stoma is 14.90-25.40 μm, and the width is 9.76-17.49 μm. According to the micromorphological characteristics of leaf epidermis, the species of Physospermopsis can be distinguished. (3) P. obtusiuscula and P. kingdonwardii are two independent species with the closest relationship. (4) Pollen morphology and leaf epidermis micromorphology have important reference value for solving the interspecific classification of Physospermopsis.

Abstract:In order to provide a theoretical basis for better protection and utilization of the plant resources of Calanthe, we observed the microstructure, invasion pathway and distribution characteristics of mycorrhizal fungi roots of five species of Calanthe by paraffin section method. The results showed that: (1) the roots of five species of Calanthe were composed of the velamina, cortex and stele. The velamina consisted of 3-6 layers of cells, the cortex was composed of 9-13 layers of parenchymal cells, the phloem and xylem are 8-12 bundles, arranged radially, and the pith was located in the center of the stele. (2) The hyphae invades the cortex through passage cells in the exodermis. The cortex is the main colonization area of endomycorrhizal fungi, Most of the hyphae and hyphae were found in several layers of cortical cells near the exodermis. The hyphae is digested near the nucleus and the nucleus is deformed and expanded. According to the research, the five species of Calanthe may have a wide range of mycorrhizal fungal types, which make these five species of Calanthe have strong ecological adaptability.

Abstract:The flowering process and pollinators of Paeonia ludlowii, an endemic plant in Tibet, which introduced and cultivated in Luanchuan County, Henan province were observed in 2019 and 2020. Pollenovule ratio(P/O), outcrossing index (OCI), pollen viability and stigma receptivity, artificial pollination were used to study flowering characteristic and breeding system type. The result showed that: (1) P. ludlowii flowers bloomed during the day and closed at night, the flowers tilted down as corolla unfolded and tilt upward as corolla closed. (2) Flowers lightly fragrance with intrafloral nectary, the main secreting site was between petal and ovary. (3) The florescence of group was from May 17 to June 19 in 2019, lasting 35 days, which was a concentrated flowering pattern, well a single flower bloomed (8.95±1.28) d. (4) The pollen activity was high from the 2nd day to the 6th day in florescence, the stigma got receptivity 1 day before flowering and lasted for 12 days. (5) The P/O was 119 356.31-731 238.07, OCI was 4, its breeding system type is outcrossing, partial selfinbreeding, and pollinators were required. (6) it may have unstable apomixis, and emasculation will severely affecting seed setting. (7) The main pollinators were Apismellifera ligustica, Ceratina sp., Halictus sp., Eristalis cerealis and Episyphus balteatus. Among them, A. ligustica visited flowers most frequently. (8) The seed setting of side flowers were more stable than that of top flowers, it is recommended to pollinate side flowers on the 3rd and 4th day in florescence to obtain a higher seed setting rate in crossing breeding.

Abstract:We used Lilium pumilum bulbs and cherry tomato (Lycopersicon esculentum var. cerasiforme) as the experimental materials to analyze the effects of L. pumilum bulb extracts in different concentrations (0~1.0 g/L, without any treatment for the control group) on fruit sensory quality, nutritional quality and superoxide dismutase (SOD) activity during storage at low temperature (5 ℃) and room temperature (20 ℃). A colorimetric method combined with a turbidimetric method was employed to determine the contents of active ingredients in the L. pumilum bulb extracts and the antioxidant capacity as well as antibacterial activity, and to investigate the preservation effects of the L. pumilum bulb extracts on cherry tomato. Results revealed as follows: (1) with 0-1.0 g/L L. pumilum bulb extracts soaking cherry tomato, then cherry tomatoes were stored at 5 ℃ for 21 d and at 20 ℃ for 35 d, respectively, and accordingly under such circumstances the storage periods were 3~6 d and 7~14 d, respectively, longer than that of the control group. (2) The L. pumilum bulb extracts both in the appropriate concentration (0.4~0.8 g/L) at 5 ℃ and in various concentrations at 20 ℃ inhibited the decrease in cherry tomato firmness effectively, delayed the increase in mass loss rate and chroma, and additionally both at 20 ℃ and at 5 ℃, the effects of 0.8 g/L were the best. At the end of storage, mass loss rate and chroma at 20 ℃ (5 ℃) storage temperatures were significantly lower than those of the control by 70.27% (58.82%) and 93.44% (89.33%), while the firmness at both storage temperatures was significantly increased by 81.11% (69.78%). (3) Both the L. pumilum bulb extracts in the appropriate concentration at 5 ℃ and those in various concentrations at 20 ℃ significantly delayed the consumption of vitamin C (Vc) and total acid (TA) in cherry tomato, and the increase in soluble solids (TSS) content, while at 20 ℃ and at 5 ℃, the effects of 0.8 g/L were the best. At the end of storage, the contents of TA and Vc in cherry tomato stored at 20 ℃ (5 ℃) were significantly higher than that of the control by 65.59% (65.06%) and 70.87% (53.44%), while the content of TSS was significantly reduced by 93.49% (84.62%). (4) The L. pumilum bulb extracts in the appropriate concentration at 5 ℃ and those in various concentrations at 20 ℃ effectively delayed the decrease of SOD activity, while at 20 ℃ and at 5 ℃, the effects of 0.8 g/L were the best. At the end of storage, the SOD activity in cherry tomato at 20 ℃ (5 ℃) were significantly increased by 66.42% and 70.80%, respectively in relation to that of the control. (5) The 0.8 g/L lily bulb extracts were rich in polysaccharides, flavonoids, flavanols, saponins, total phenols, alkaloids and other active ingredients (0.34~2.41 mg/g), which had the scavenging capacity up to 7.10 μmol/g and 1.06 μmol/g for DPPH and copper ion, respectively, and the significant inhibitory effect on the growth of Penicillium on tomato. The number of Penicillium was effectively lower than that of the control by 74.44%~79.76%. The present study demonstrated that the extracts of L. pumilum bulbs were rich in polysaccharides, saponins, polyphenols and other active ingredients, which had efficient antioxidant and antibacterial activities. Also, the appropriate concentration of L. pumilum bulb extracts could effectively reduce the mass loss rate of cherry tomato, maintain the firmness and chroma of cherry tomato, preserve the nutritional components such as vitamin C, total acid and soluble solids, and prolong storage time evidently, and exhibit good freshness preservation effects, with the concentration of L. pumilum bulb extracts at 0.8 g/L having the best freshkeeping effect.

Abstract:The aim of this study is to uncover young shoot pigment changes of albino tea plant (Camellia sinensis) cultivar ‘Zhonghuang 3’ (‘ZH3’) and their correlation with main biochemical components accumulation. With the evergreen ‘Taicha 15’ (‘TC15’) strain as the control, we determined and analyzed the dynamic changes of pigments and main biochemical components in young shoots (one bud and two leaves) from two resources sampled in April, May, July and August. The content of chlorophyll a and total chlorophyll in two resources initially increased and then decreased, while chlorophyll b content showed a different trend, and three physiological indicators reached its peak in August. Chlorophyll b content of ‘ZH3’ in April and May was 41.9% and 54.9%, respectively, lower than that of ‘TC15’, while that of ‘ZH3’ in July and August was 47.5% and 22.1%, respectively, higher than that of ‘TC15’. Carotenoids content of ‘ZH3’ decreased gradually, while that of ‘TC15’ first decreased, then increased and subsequently decreased. Anthocyanin content in two resources initially increased and then decreased. In April, May and August, anthocyanin content of ‘ZH3’ was slightly higher than that of ‘TC15’, but 26.4% lower than that of ‘TC15’ in July. The proportion of anthocyanin in two resources increased first and then decreased, whereas the opposite trend was observed for that of total chlorophyll. The proportion of carotenoids in ‘ZH3’ showed a decreased trend, while that in ‘TC15’ decreased first and then increased slightly. Free amino acids content in two types of tea plants was the highest in April, and showed a trend of decreasing first and then increasing, while the content of tea polyphenols reached the maximum value in July, and showed the opposite trend. No significant changes of water extracts and caffeine contents in ‘ZH3’ among different months were observed. Free amino acids, water extract and caffeine content in ‘ZH3’ was not significantly correlated with pigments content. Tea polyphenols content in ‘ZH3’ was positively and significantly correlated with chlorophyll a, chlorophyll b and total chlorophyll content, respectively, while negatively and significantly correlated with carotenoid content. Positive significant correlations between anthocyanin content with water extract and tea polyphenol content were observed for ‘TC15’. Free amino acid content in ‘TC15’ had positive correlations with total chlorophyll content. There were positive correlations between caffeine content with chlorophyll a, total chlorophyll and carotenoid content in ‘TC15’. Our data suggested that the yellower young shoots color in ‘ZH3’ was the higher content of carotenoid and free amino acids, the lower content of chlorophyll a, chlorophyll b and tea polyphenols, the high chlorophyll a/b ratio, and the moderate anthocyanin content. There existed a very close relationship between pigments and biochemical components in young shoots of tea plant.

Abstract:In order to determine the core quality index of Cabernet Sauvignon wine grape in Hexi Corridor, we established a comprehensive evaluation model for Cabernet Sauvignon wine grape quality. Six samples of Cabernet Sauvignon wine grapes were collected from three representative orchards of Zhangye, Wuwei and Jiayuguan, and the quality of Cabernet Sauvignon wine grapes was determined. The core quality index of Cabernet Sauvignon wine grape was determined by principal component analysis and cluster analysis. The analytic hierarchy process was used to determine the index weight and establish a comprehensive evaluation model of Cabernet Sauvignon wine grape quality. The results showed that: (1) there were significant differences in quality indexes of Cabernet Sauvignon wine grapes from different producing areas. The contents of fructose, sucrose, oxalic acid and citric acid of the Cabernet Sauvignon grape in Guofeng Wine manor of Zhangye City were higher than those in other areas. The contents of soluble solids, soluble sugar, total phenol and malic acid were kept at a high level in each producing area. (2) Correlation analysis showed that there was a very significant positive correlation between glucose content and soluble solids content, fructose content and soluble sugar content in grape fruit. Solid ratio and sugaracid ratio were significantly negatively correlated with titratable acid content. (3) Combined with principal component analysis, cluster analysis and correlation analysis, we found Vc, tannin, fructose and solidacid ratio were determined as the core quality indexes of Cabernet Sauvignon grape. The comprehensive evaluation model for grape quality of Cabernet Sauvignon was established by analytic hierarchy process (Y=0.0960 Vc content + 0.1611 tannin content + 0.2771 fructose content + 0.4568 solidacid ratio (all index contents were standardized). It is found that Zhangye is the best Cabernet Sauvignon grape producing area for fruit quality in Hexi Corridor. Fruit Vc, tannin, fructose and solidacid ratio are the core quality indexes of the Cabernet Sauvignon grape. The established evaluation model can be used to comprehensively evaluate the quality of the Cabernet Sauvignon grape.

Abstract:The soil is poor and soil erosion is strong in the sandstone area of Ordos Plateau, and soil nitrogen literacy is also the main limiting factor of vegetation restoration and reconstruction in this area. The study included three native species of Achnatherum splendens, Amygdalus pedunculata and Hippophae rhamnoides, and two exotic species of Rheum palmatum and Pennisetum americanum×P. purpureum as the subject. Using field test methods, we analyzed and compared the differences of individual growth performance and nitrogen utilization related indicators with these five potentially suitable plants in 4 nitrogenapplying levels ［control N₀, low nitrogen (N_L, 0.1 g N/kg), medium nitrogen (N_M, 0.2 g N/kg) and high nitrogen (N_H, 0.3 g N/kg), under airdried soil］. The aim is to provide theoretical basis for regional vegetation restoration and reconstruction from the perspective of nitrogen utilization and species selection and nitrogen application intervention.The results showed that: (1) the individual growth performance of the five plants was the best under the medium nitrogen level compared to other nitrogen levels. When the R. palmatum, A. splendens, A. pedunculata, P. americanum×P. purpureum and H. rhamnoides were at the medium nitrogen level, the plant height and biomass increased by 10.00, 41.41, 38.95, 151.45, 41.08 cm and 52.84, 60.55, 75.36, 668.67, 142.86 g, respectively. (2) The average nitrogen utilization efficiency (NUE) of 5 plants at 4 nitrogen levels was 1 154.42 g·g^-1, under each nitrogen level, the NUEs of H. rhamnoides, R. palmatum, A. pedunculata, P. americanum×P. purpureum and A. splendens are 1 546.16, 1 429.45, 1 389.75, 731.09, 675.65 g·g^-1, respectively; there are significant differences in NUE among the five plants. The comprehensive NUE performance of the plants at each nitrogen level is: H. rhamnoides, A. pedunculata, R. palmatum > P. americanum×P. purpureum, A. splendens. (3) The effect of nitrogen level on NUE in 5 plants was significant. The highest under medium nitrogen application, and the NUE of different nitrogen application levels in 5 plants was shown as: medium nitrogen > control, high nitrogen > low nitrogen. (4) Among the two multiplying factors that affect NUE, five plants showed a clear tradeoff between nitrogen productivity (NP) and residence time (MRT) due to differences in life forms. Among them, P. americanum×P. purpureum introduced as a fastgrowing plant tends to increase nitrogen use efficiency by increasing nitrogen productivity; while native species of large shrubs, H. rhamnoides and A. pedunculata tend to increase nitrogen use efficiency by increasing residence time. According to the research, it is suggested to plant H. rhamnoides and A. pedunculata in the selection of vegetation restoration species and nitrogen intervention in the sandstone area, and the moderate nitrogen use can help improve the efficiency of nitrogen utilization of regional suitable plants and promote vegetation restoration and reconstruction.

Abstract:Five typical bloom algae species (Chlorella, Chlamydomonas, Cyclotella, Synedra, Glenodinium) in the source water of villages and towns in the Three Gorges Reservoir area were selected as materials. The effect of different doses of PAC (poly aluminum chloride) on the removal of these algae cells (chlorophylla and turbidity), as well as the differences in the structure and morphology of the flocs after coagulation and sedimentation, were compared, and the appropriate PAC dosage for removal the coagulation of typical algae species was screened. The results showed that: (1) the morphological structure of the selected algae species in the experiment are obviously different, Synedra has a long linear structure, Cyclotella has a short cylindrical structure, and Chlorella, Chlamydomonas and Glenodinium are spherical or elliptical. Cells of Synedra and Glenodinium are relatively the largest. (2) The PAC removal efficiency of Synedra and Glenodinium was the best, followed by Chlorella and Chlamydomonas, while the good PAC removal efficiency of Cyclotella was relatively difficult to achieve. The removal efficiency of PAC is related to the morphological characteristics of algae. (3) Synedra and Glenodinium were prone to form large and dense flocs. Chlorella and Chlamydomonas formed relatively small flocs, and Cyclotella has the weakest ability to form flocs. (4) The appropriate dosage of PAC was 15-80 mg/L for Synedra and Glenodinium, 15-50 mg/L for Chlorella, 15-65 mg/L for Chlamydomonas and 50-80 mg/L for Cyclotella. Within the appropriate PAC dosing range, the removal rates of Chla and turbidity of each algae reached 81%-97% and 76%-97%, respectively. It can be seen that the PAC coagulation sedimentation method can be used to remove 5 typical blooms and algae species in the water source water of villages and towns in the Three Gorges Reservoir area, but the appropriate dosage of each algae species is different. Appropriate amount of PAC can effectively reduce the Chla and turbidity in each algae liquid.

Abstract:In order to understand the dynamics of soil carbon in mountain forests with different precipitation gradients, we selected the soil samples of Picea crassifolia and Pinus tabuliformis in Helan Mountains, Luoshan Mountains and Liupan Mountains in Ningxia as the research objects. The vertical and horizontal distribution of soil organic carbon characteristics ［soil organic carbon (SOC), stable carbon isotope composition (δ¹³C) and β value］ in Picea crassifolia and Pinus tabuliformis were analyzed, and the effects of soil chemical indexes on soil organic carbon (SOC) characteristics were investigated by redundancy analysis. We explored the characteristics of soil stable carbon isotopes in arid and semiarid regions, in order to provide a basis for revealing the dynamic change of soil carbon in mountainous forests in arid regions.The results showed that: (1) with the increase of precipitation in the sample land, the soil SOC content of both Picea crassifolia and Pinus tabuliformis increased gradually, while the soil δ¹³C and β values decreased gradually. Under the same precipitation condition, Picea crassifolia was more conducive to soil organic carbon accumulation than Pinus tabuliformis. (2) The SOC content of both Picea crassifolia and Pinus tabuliformis decreased with soil depth increasing, while the δ¹³C of both increased with soil depth increasing. (3) Redundancy analysis between soil organic carbon characteristics and soil chemical indexes of Picea crassifolia and Pinus tabuliformis forests in Helan, Luoshan and Liupan in Ningxia revealed that alkalihydrolyzale nitrogen was the dominant factor affecting soil organic carbon distribution characteristics.

Abstract:The phenotypic diversity of the flowers and leaves of three Rosa odorata var. gigantea populations containing 240 plants in Liangwang Mountains, Chengjiang City, Yunnan Province were analyzed by means of nested variance analysis, phenotypic variation coefficient analysis and Pearson correlation analysis. The results showed that there was abundant phenotypic diversity within and between populations, and the phenotypic differentiation coefficient ranged from -1.51% to 26.18%. In the close distance, the intrapopulation diversity was much higher than the interpopulation diversity. The mean coefficient of variation of phenotypic traits within populations was 13.62%, and the dispersion degree was relatively low. Among them, the largest differentiation coefficient was the length of peduncle, and the smallest was the ratio of petal lengthwidth. The correlation analysis showed that the correlation between most flowerrelated traits was strong and the same is true for most leafrelated traits, while the correlation between flowerrelated traits and leafrelated traits was low or even irrelevant.

Abstract:In this study, the species diversity and geographical distribution pattern of wild Impatiens in Guizhou Province were studied based on the establishment of a list and geographical distribution database of wild Impatiens in Guizhou Province. Through the literature and a field investigation, we analyzed the species composition, endemism, horizontal distribution, vertical distribution and similarity. Finally, the hotspots of Impatiens in Guizhou were determined by a complementary algorithm，This study is of great significance to the conservation and sustainable utilization of Impatiens plant resources in Guizhou Province. The results show that: (1) there are 60 species (including subspecies) of Impatiens in Guizhou Province. These plants are distributed among 69 countylevel administrative districts. There are 55 species endemic to China and 10 endemic to Guizhou, and the vertical distribution is the most abundant at altitudes of 1 000~1 500 m. (2) The calculation of the provincial similarity coefficient showed that Guizhou and Hunan had the highest similarity. Finally, 9 hot spots were selected, representing 86.67% of the Impatiens plants. (3) Guizhou Province has a warm and humid climate with typical karst landforms, which have abundant Impatiens plant and have high species diversity and regional specificity.

Abstract:Geographic factors play an important role in the species distribution and divergence of natural populations in plants. Here we reanalyzed 14 SSR markers data in 39 populations from Fargesia spathacea complex, aimed to reveal how geographic factors may influence the pattern of genetic diversity and divergence of F. spathacea complex. The results showed that: (1) we found that F. scabrida subclade exhibited the highest genetic diversity (H_e=0.50), while F. obliqua subclade exhibited the lowest one (H_e=0.33). (2) On the level of clade A and B, genetic diversity was proved to be significantly positive correlated to altitude and latitude; but on the level of subclade, we detected negatively correlations between genetic diversity and altitude, latitude, which indicated that some other factors may have an impact on the genetic diversity within F. spathacea complex. (3) We carried out Mantel test and found that geographic distance may not be the driving force of the current genetic divergence pattern within F. spathacea complex. Clade B showed no significant correlation between genetic distance and geographic distance, and only one subclade in clade A showed slightly significant correlation. Future studies of gene flow may help answer whether hybridization influenced the genetic differentiation within these species.

Abstract:In order to explore the competitive relationship in Platycarya longipes community in Karst area, this study investigated 36 objective trees and 1 502 competitive trees in P. longipes community in Maolan National Nature Reserve. The intraspecies and interspecies competition intensities of P. longipes were calculated combined Hegyis individual tree competition index. The results showed: (1) the intraspecies competition of P. longipes (387.05) was significantly higher than interspecies competition (226.19) (P< 0.01). Its competitive pressure mainly comes from intraspecies competition. (2) There are 59 species of P. longipes associated trees, the species with competition index > 5 were Carpinus pubescens > Pinus kwangtungensis > Liquidambar formosana > Lindera communis > Myrsine seguinii> Pistacia weinmanniifolia > Castanopsis echidnocarpa > Cyclobalanopsis myrsinifolia > Tirpitzia sinensis > Celtis sinensis. (3) The competition index between P. longipes and the whole stand, associated tree species and intraspecies was a power function relationship (CI=aD^b). The larger the DBH of P. longipes, the less the competition pressure was. (4) The competition model predicted that with the increase of the DBH of P. longipes, the competition index of P. longipes decreased within species, between species and the whole stand. When the DBH of P. longipes is greater than theⅠdiameter class (DBH < 3 cm), the interspecies competition pressure becomes smaller, and when the DBH is greater than the Ⅱ diameter class (3 cm≤DBH < 6 cm), the intraspecies competition pressure becomes smaller. When DBH was larger than the Ⅲ diameter class (6 cm≤DBH < 9 cm), the competitive pressure of the whole stand decreased, indicating that P. longipes had higher competitive ability in the middle and small size class. The results showed that P. longipes, as the building species, played an important role in both the development and stability stages of the community, and was more adaptable to the environment in the karst area, and had a great advantage in the evolution of the community, which laid a theoretical foundation for revealing the position and mechanism of P. longipes in the karst forest.

Abstract:Agapetes putaoensis Y. H. Tong & N. H. Xia was originally described from Putao District, Kachin State, northeast Myanmar in 2014. The present authors collected it from Lüchun County, Yunnan, China in 2018 and 2020. Here, it is reported as a newly recorded species for China. This species is described and illustrated with a colour plate for identification. Supplementary description of its fruits is also provided. The voucher specimens are deposited in the Herbarium of Xishuangbanna Tropical Botanical Garden (HITBC) and the Yunnan Branch, Institute of Medicinal Plant, Chinese Academy of Medical Sciences (IMDY).

Abstract:By sorting out the data of ferns and investigating in the fields of Qinling Mountains, we found a new record genus of ferns—Struthiopteris, whose genus is Struthiopteris eburnea, which further enriched and perfected the records of fern species in Qinling Mountains in Shaanxi Province. The paper described its characteristics of morphology and habitat in Qinling Mountains. The specimens are kept in the herbarium of Hunan University of Human Science and Technology.

Abstract:In this article, we tracked down the collecting locality of the holotype specimen of Allium rhabdotum Stearn (Amaryllidaceae), and proved that its type locality lies within Cona County, Xizang Autonomous Region, Peoples Republic of China, rather than within the Kingdom of Bhutan; thus A. rhabdotum has never been endemic to Bhutan. Recent collections of A. rhabdotum in Lhünzê County, Xizang were also reported here, providing new information to the species distribution. We named the plant in Chinese and supplied its morphology and habitat description, as well as discussed its diagnostic characters, phylogenetic position, exploitability, conservation status, and potential distribution.