Abstract:[Objective] To explore the mechanism of water saving and water control methods to regulate the efficient use efficiency of apple water, and optimize the management methods of water saving, high yield and income increase in Weibei apple main producing area. [Methods] The eight-year-old 'Yanfu 3 /T337' apple tree was selected from the experimental station of Tiefu town, Xian County, Xianyang City, Shaanxi Province Xi 'an Fruit Friends Association, and two irrigation water levels were set: Full irrigation (relative water content of soil after irrigation: 75%) and slight deficit irrigation (relative water content of soil after irrigation: 50%).There were four irrigation modes: full irrigation at both fruits growing and expanding stages (CK), light deficit irrigation at both fruits growing and expanding stages (W1), light deficit irrigation at fruits growing and expanding stages (W2), and light deficit irrigation at fruits growing and expanding stages (W3). Spring shoot growth index, fruit quality index and fruit yield index were determined, to calculate water use efficiency, irrigation water use efficiency and fruit comprehensive evaluation satisfaction to determine the best deficit irrigation method. [Results] (1) There were no significant differences in shoot length and leaf chlorophyll relative content (SPAD) among different irrigation modes, but the diameter of spring shoot decreased significantly under different deficit irrigation. (2) Compared with CK, the single fruit weight was significantly reduced by 10.3% under W1 water deficit irrigation treatment, the titrable acid content of fruit was significantly reduced by 14.7% under W2 treatment, and the fruit shape index and soluble solid content were not significantly changed under the three water deficit treatments. (3) W1 deficit irrigation treatment can significantly increase the peel yellow value b*, W2 irrigation treatment can significantly increase the peel color saturation C*, but deficit irrigation treatment has no significant effect on the peel brightness value L* and red green value a*. (4) Compared with CK, fruit yield decreased by 13.4%-24.7% under each treatment, but only W1 treatment reached a significant level; The fruit tree irrigation water use efficiency increased in different degrees in each deficit irrigation treatment, but only W1 treatment significantly increased by 38.0%. There was no significant difference in water consumption and water use efficiency of fruit trees under each treatment. The satisfaction of fruit comprehensive evaluation was W2 > CK > W3（W1）. [Conclusion] According to the comprehensive evaluation, the comprehensive evaluation satisfaction of apples in Weibei area of Shaanxi province was the highest under mild deficit irrigation in growth period and full irrigation in expansion period (W2). There was no significant change in fruit yield and single fruit weight, but the fruit quality was better and the water use efficiency of fruit trees was higher.

Abstract:【Objective】 Atriplex canescens is a high-quality xerophytic shrub widely introduced in desertification control areas. Stubble is its main tending management measure. Revealing the adaptability and compensatory growth mechanism in the recovery process after stubble can provide theoretical support for the development of Atriplex canescens into high-quality feed in desert areas. 【Method】 In this experiment, 5-year-old Atriplex canescens plants were used as the research object. Through the stubble treatment, the plant height, crown width, photosynthetic reaction, leaf water potential, leaf hydraulic conductivity and water use efficiency were measured during the recovery process of Atriplex canescens, and the relationship between functional traits was discussed. 【Results】 ( 1 ) The plant height, crown width and aboveground biomass of A.canescens after stumping could recover to the pre-stubble state after a growing season. ( 2 ) The leaf water potential, leaf hydraulic conductivity, water use efficiency and photosynthetic parameters of the stubble plants were higher than those of the control plants. ( 3 ) Linear fitting analysis showed that the midday leaf water potential and stomatal conductance of the stubble plants were significantly positively correlated with the growth rate. 【Conclusion】 Atriplex canescens has good compensatory growth ability after stumping. In the early stage of recovery growth, the flat stubble plants showed higher compensatory growth ability and typical acquisition strategy, and then turned to conservative strategy with the decrease of hydraulic condition in the later stage. Stubble plants will allocate more biomass and resources to the growth of aboveground tissues such as branches and leaves, and the later resource allocation will turn to promote the growth of underground parts.

Abstract:[Objective] Grain size significantly influences the yield, marketability and processing attributes of quinoa. studying the differences of seed phenotypes, filling characteristics and starch synthase activity of large- and small-grained quinoa during the filling period to provide theoretical guidance for the selection and breeding of large-grained quinoa varieties. [Methods] Two quinoa samples, one with a thousand grain weight exceeding 5.0 g and the other is below 3.0 g, were selected for a field experiment at the Innovative Experimental Base of Germplasm Resources of Qinghai Academy of Agricultural and Forestry Sciences. The study comparing the differences in grain phenotypes, filling characteristics, and starch synthase activity between large- and small-grained quinoa at 7, 14, 21, and 28 days of the during the filling stage. [Results] (1) The phenotypic traits of large- and small-grained quinoa characteristics, including grain area, circumference, diameter, kernel length, and kernel width, significantly increased with reproductive period, and there were significant differences between grain types, the largest differences were in seed area and circumference, with large-grained quinoa being significantly higher than small-grained quinoa by 9.12% to 11.54% and 21.49 to 23.92%, respectively. (2) Throughout the filling period, the dry weight of 100 grains of large-grained quinoa consistently exceeded that of small-grained quinoa in the same period, with an average increase of 21.23% to 31.04%; the filling rate of large and small-grained quinoa first rose and subsequently declined during the reproductive period, which was in line with the pattern of change of "slow-fast-slow", however the time to reach the peak and the peak height were obviously different, with large-grained quinoa appearing early and high, while small-grained quinoa was low and late. The peak of large grain appeared early and high, while small grain was low and late. (3) The starch branching enzyme (SBE), sucrose synthase (SS), soluble starch synthase (SSS) and ADPG pyrophosphorylase (AGP) varied during for both grain sizes, with SBE and SS activities being stronger in small-grained quinoa than in large-grained quinoa, while SSS and AGP activities were stronger in large-grained than in small-grained quinoa. [Conclusion] Variations in the activities of four starch synthases during quinoa grain filling contribute to differences in the accumulation of starch synthesis and peak filling rate, which in turn leads to differences in grain phenotypic traits, whereas SSS and AGPase are the key enzymes affecting quinoa grain size formation.

Abstract:The purpose of this experiment was to explore the effects of Melatonin (MT) application in the rhizosphere, inoculation of Claroideoglomus etuncatum and its combined treatment on the growth, chlorophyll fluorescence parameters, hormone metabolism and antioxidant system of rose seedlings under 100 mol/L salt stress, so as to explore the mechanism of both alleviating the salt stress of rose. The results showed that under salt stress, the growth of rose seedlings was inhibited, and plant height, stem diameter, and biomass significantly decreased; The application of MT can promote AMF infection, increase the infection rate, clump growth rate, number of vesicles, and number of invasion points. Under 100mol/L salt treatment, compared with the control (CK) treatment, the total chlorophyll content and chlorophyll a/b of AMF+MT treatment increased by 46.2% and 67.2%, respectively; The maximum photochemical efficiency (Fv/Fm), potential activity (Fv/Fo), and actual photochemical efficiency of PS II in chlorophyll fluorescence parameters(φPSII), PSII effective photochemical quantum efficiency (Fv "/Fm"), and photochemical quenching coefficient (qP) increased by 4.9%, 51.0%, 175.0%, 168.7%, and 92.5%, respectively, with a decrease in NPQ of 42.7%; In addition, under salt stress, the contents of zeatin nucleoside (ZR), gibberellin (GA), and auxin (IAA) in rose leaves decreased, while the content of Abscisic acid (ABA) increased. After AMF+MT treatment, ZR, GA, and IAA increased by 146.9%, 116.9%, and 35.7%, respectively, and ABA decreased by 21.1%; At the same time, AMF+MT treatment can activate the activities of antioxidant enzymes SOD and CAT, reduce the rate of superoxide anion (O2-) production and H2O2 accumulation. The conclusion is that the inoculation of AMF, the addition of MT or AMF+MT can increase the chlorophyll content, protect the chlorophyll fluorescence system, maintain the balance of plant endogenous hormones, activate the activities of SOD, CAT and other antioxidant enzymes, and reduce the accumulation of Lipid peroxidation and H2O2, so as to alleviate the damage of salt stress to the monthly seedlings and promote the growth of roses. The effect of AMF+MT treatment on the salt resistance of rose seedlings is better.

Abstract:【Objective】NAC transcription factor family is a class of transcription factors that are widely studied in plants. It plays an important role in regulating plant growth and development and responding to abiotic stress. Maize is one of the three major food crops, which will face various adverse stresses in its growth process. Salt damage is considered to be one of the main environmental factors limiting crop growth and production. Therefore, it is of great significance to identify maize salt resistance genes and analyze their salt resistance mechanism for breeding maize stress resistant varieties. 【Method】This study cloned the maize transcription factor ZmNAC59 and analyzed its conserved domain and phylogenetic relationship using bioinformatics methods. The expression pattern of the gene in leaves under NaCl and MeJA treatment was analyzed using the Quantitative Real-time PCR method. The stable transgenic system was used to heterologously express the gene into Arabidopsis for phenotype observation. At the same time, virus-induced silencing technology was used to silence the gene in maize, followed by salt treatment phenotype observation and enzyme activity detection. 【Result 】The qRT-PCR results showed that ZmNAC59 could be up-regulated by NaCl and MeJA. After virus-induced silencing of ZmNAC59, the silenced strains were more sensitive to salt stress and accumulated more ROS. After overexpression of ZmNAC59 in Arabidopsis thaliana, the overexpression lines had higher survival rate, less accumulation of reactive oxygen species and lower Na+/K+ ratio under salt stress, indicating that ZmNAC59, as a positive regulator of salt stress, can improve plant salt resistance by regulating ion flow. qRT-PCR results showed that Na+, K+ transport related genes were significantly up-regulated in Arabidopsis overexpression lines; After transient overexpression of ZmANC59 in maize protoplasts, the expression of ZmSOS1, ZmNHX1 and ZmNHX7 were significantly up-regulated after salt treatment. The Dual-Luc experiment showed that ZmSOS1 was the target gene of ZmNAC59. 【Conclusion】 This study found that ZmNAC59 could promote ion transport under salt stress by activating the expression of ZmSOS1, which provided a scientific theoretical basis for the screening of maize stress resistance gene resources and cultivar cultivation.

Abstract:【Objective】 Sugars will eventually be exported transporters (SWEETs) play an important role in the growth and development of plants. The aims of the study were to elucidate the role of SWEETs genes family in sugar accumulation during the development of wolfberry, and provide a reference for revealing the role of SWEET gene in the development of Lycium barbarum L. fruit. 【Methods】 In the present study, based on genomic data of L. barbarum L., the SWEET gene (LbaSWEET) of L. barbarum L.was identified by bioinformatics method, and the expression of LbaSWEET during fruit development was analyzed using published transcriptional data. 【Results】 The results showed that there were 37 members of the SWEET gene family, which were randomly distributed on 10 chromosomes, encoding 152-621 amino acids, respectively. The molecular weight of the protein was 16.87-69.97 kD, and the isoelectric point was 4.96~9.86. Subcellular localization is predicted to be located in the chloroplast or plasma membrane, most containing seven transmembrane helices. Phylogenetic analysis indicated that 37 LbaSWEET proteins could be divided into four subgroups, each of which had similar gene structure and conserved motif composition. The analysis of promoter elements showed that LbaSWEET gene promoter was rich in hormone response, stress response and growth response elements. Transcriptome data and qRT-PCR analysis showed that the expressions of LbaSWEET9 and LbaSWEET29 genes increased significantly with fruit ripening. Pearson correlation analysis showed that the expression levels of LbaSWEET9 and LbaSWEET29 genes were significantly positively correlated with fructose content. 【Conclusion】 It is speculated that LbaSWEET9 and LbaSWEET29 are the key genes that played an important role in the accumulation of fructose sugar.

Abstract:【Objective】 This study aims to examine the expression pattern of the PYL gene in Luffa cylindrica after ABA treatment. 【Methods】 Bioinformatics methods were used to analyze the distribution, chromosome location, gene structure, gene collinearity, selection pressure analysis, evolutionary relationships, and cis-acting elements of the PYL gene family in the whole genome of Luffa cylindrica cucumis. The expression specificity of the PYL gene family under different concentrations of ABA was then verified by qRT-PCR. 【Results】 Eleven LcPYL genes were identified within the entire genome of Luffa cylindrica. These genes correspond to CDS lengths of 576-966 bp and all possess typical PYR_PYL_RCAR-like structures. Collinearity analysis reveals that 7 pairs derived from genome-wide duplication events are expected to have similar biological functions. The PYL gene promoter in Luffa cylindrica contains several cis-acting elements associated with plant hormones, and the expression of its members shows certain tissue specificity. The expression of LcPYLs in Luffa cylindrica fruit did not exhibit significant changes when treated with 2 mg/ml ABA, However, the expression of LcPYL5, LcPYL7 and LcPYL11 significantly increased after 4 mg/ml ABA treatment, LcPYL1 and LcPYL7 were significantly expressed on the day of flowering post 8 mg/ml ABA treatment. 【Conclusion】 In this investigation, we conducted a systematic identification and analysis of PYL family members within Luffa cylindrica in order to establish their molecular structure and expression patterns. Our findings suggest that LcPYL1, LcPYL5, LcPYL7, and LcPYL11 are potentially crucial genes that are closely linked to endogenous ABA biosynthesis.

Abstract:【Objective】 Chlorophyllide a oxygenase (CAO) is a key enzyme in the formation of chlorophyll b. To investigate the regulation function of the CAO gene in the leaf color variation of Cymbidium hybrid, and to provide an important basis for studying the formation mechanism of leaf art. 【Methods】 ChCAO gene was cloned from leaves of Cymbidium hybrid by RACE and RT-PCR methods. ChCAO was analyzed for structure characteristics, physicochemical properties, sequence alignment and phylogenetic relationship. The expression characteristics of ChCAO in different tissues and leaves of K21-3 were analyzed by qRT-PCR. 【Results】The results showed that ChCAO coding region was 1 608 bp long, which encoding 535 amino acids. ChCAO was closely related to Cymbidium sinense, which also belonged to genus Cymbidium. The qRT-PCR results reflected the tissue-specific in the expression of ChCAO, with the highest relative expression in leaves and the lowest in roots. Among the different varieties, the expression level of ChCAO in K21 leaves were significantly higher than that of K21-3. The VIGS silencing vector of this gene was constructed and transferred to tobacco, it was found that the viral vector successfully invaded the body of tobacco, the old leaves of tobacco were in a yellow state, and the chlorophyll content in the old leaves and the relative expression of the ChCAO gene were also significantly reduced. It is speculated that the silent expression of ChCAO gene may lead to the reduction of chlorophyll content and the yellowing of leaves, which preliminarily clarifies the function of the ChCAO gene in Cymbidium hybrid.

Abstract:【Objective】As a kind of thermophilic and chilling-sensitive plants, low temperatures severely affect the growth, development, geographical distribution, and yield of Jatropha curcas L. Previous studies have found that chill-hardening at 12°C can significantly enhance the chilling resistance of J. curcas. The Early Light-Inducible Protein (ELIP) gene in J. curcas is a highly responsive gene to low temperatures. To explore the role of JcELIP in response to low temperatures in J. curcas, to comprehensively understand the structure, regulatory mechanisms, evolutionary relationships of JcELIP, and its interaction with miRNAs, and to provide an important candidate gene resource for subsequent molecular breeding of cold resistance in J. curcas. 【Methods】 This study cloned the JcELIP gene from J. curcas by RT-PCR and conducted a comprehensive bioinformatics analysis. The expression changes of the JcELIP gene in the roots, stems, and leaves, as well as during the chill-hardening at 12°C, were analyzed by RT-qPCR. The miRNAs interacting with JcELIP were identified, and a co-expression analysis was conducted during the chill-hardening at 12°C. 【Results】 The results showed that the complete open reading frame (ORF) of the JcELIP is 585 bp, encoding 194 amino acids. The size of the protein is 2.04 kD with a theoretical isoelectric point of 9.59. It is a stable hydrophobic alkaline protein, with 3 hydrophobic transmembrane helices. The tertiary structure mainly consists of α-helices and irregular coils and possesses chlorophyll a/b binding sites. Cis-acting element prediction shows that JcELIP has hormone response elements such as abscisic acid. Evolutionary analysis showed that the JcELIP from J. curcas has the highest homology with MeELIP from Manihot esculenta. RT-qPCR analysis revealed that under normal growth conditions, there is no significant difference in the expression of JcELIP in the roots, stems, and leaves of J. curcas; During the chill-hardening at 12°C, the expression of JcELIP in the leaves quickly up-regulated, reaching 64.8 times of the control at 48 h, indicating that JcELIP is involved in the response and adaptation of J. curcas to cold stress. Based on the degradome data of J. curcas, eight miRNAs, including miR390-x, miR6476-x, and novel-m0090-3p, were identified as having regulatory effects on the expression of JcELIP. Co-expression analysis showed that the expression of JcELIP was significantly negatively regulated by miR390-x and novel-m0090-3p during the chill-hardening at 12°C.

Abstract:【Objective】 The aims of the study is to figure out the role of acyl-CoA synthetase in dencicine (β-N-oxalyl-L-α, β-diaminopropionic acid, β-ODAP) biosynthesis. 【Methods】acyl-activating enzyme (AAE) superfamily genes were identified in the genome of grass pea (Lathyrus sativus L.) using the AMP binding domain hidden Markov model. After that, the acyl-CoA synthase gene was cloned and analyzed via multiple sequence alignment, prokaryotic expression and enzyme activity detection. 【Results】 The results showed that not less than 22 AAE family genes were located on 7 different branches in grass pea; phylogenetic analysis indicated that LsAAE3 and AtAAE3 (Arabidopsis thaliana) gathered to one branch and be subsumed to acyl-CoA synthetase family. Cloning and sequence analysis manifested that the full-length cDNA of LsAAE3 was 1 566 bp, LsAAE3 and AtAAE3 possessed several conversed domains including AMP binding site, CoA binding site and AAE consensus motif. The purified protein of which molecular weight was 56 kD showed a single band via SDS-PAGE, while the same band was also detected in both induced bacterial proteins and purified recombinant proteins by Western blot, both of which suggested that the fusion protein we obtained was LsAAE3. The oxaloyl-CoA synthase activity of LsAAE3 depended on ATP and magnesium ions.【Conclusion】 In conclusion, the study identified acyl-activating enzyme (AAE) superfamily genes in the genome of grass pea and verified the oxaloyl-CoA synthase activity of LsAAE3, which paved the way for further analysis of the function of LsAAE3 in β-ODAP biosynthesis.

Abstract:[Objective] As an important regulator involved in protein synthesis and gene expression regulation, ribosomal protein is crucial for plant growth and development and stress response. In this study, a ribosomal protein family gene OsRPL36A was cloned from rice, and preliminary research was performed on its biological function, which provided a theoretical basis and research direction for the subsequent study of OsRPL36A gene function. [Methods] Bioinformatics techniques were used to analysis the gene structure, cis-regulatory elements and evolution process of OsRPL36A. Meanwhile, the gene expression level of OsRPL36A in different tissues, under diurnal rhythm, different hormones and abiotic stresses were analyzed by quantitative real-time PCR (qRT-PCR). [Results] (1) The gene OsRPL36A encoded 98 amino acids in total with a 297 bp coding region, which belonged to the ribosomal protein L36 supergene family and was named as OsRPL36A. (2) The promoter region of OsRPL36A contained 3 rhythmic expression related elements, 10 light-responsive elements, 14 hormone-responsive elements, and 27 environmental stresses response elements. (3) The expression level of OsRPL36A in leaves was relatively higher than that in other tissues and presented a typical rhythmic expression pattern; the expression level of OsRPL36A was also induced by IAA, high temperature, low temperature and osmotic stress and so on. [Conclusion] OsRPL36A was highly expressed in leaves and presented a typical rhythmic expression pattern. OsRPL36A significantly responded to IAA and might be involved in response to heat shock, low temperature, salt stress, and osmotic stress.

Abstract:【Objective】 Frost temperature thresholds of grape are the basis for frost monitoring, prediction, assessment and prevention. The study was conducted to investigate the low-temperature tolerance of the main wine grape ‘Cabernet Sauvignon’ at different development stages in the eastern foothills of Helan Mountain, and further to establish a group of frost temperature thresholds for wine grapes. The study aimed to provide the theory basis for frost prediction and prevention of wine grapes in the eastern foothills of Helan Mountain. 【Methods】 We used a field frost chamber to treat the pompom, bud, new leave, and new shoot of the main wine grape variety ''Cabernet Sauvignon'' at different developmental stages with low temperatures in the eastern foothills of the Helan Mountainduring the period of April to May 2022. The supercooling point, relative electrical conductivity (REC) and semi-lethal temperature (LT50) were measured for each treatment. And we carried out a follow-up field survey on frozen ratio after various low-temperature treatment. Then, the regression model based on the correlation between frozen ratio and low temperature was set up to calculate the critical temperatures for light, moderate and severe frost at different development stages of wine grape. The abovementioned indicators at the critical temperature of frost were comprehensively analyzed to determine the frost temperature thresholds at different development stages of ''Cabernet Sauvignon''. 【Results】 The results showed that: The low-temperatures had different effects on ''Cabernet Sauvignon'' during the pompom, bud opening, leaf spreading and new shoot growth stages. The lower the temperature was, the higher the frozen ratio at the different stages was. The supercooling point and the semi-lethal temperature (LT50) were gradually increasing as the development of wine grape progresses. The low temperature tolerance in the pompom stage was the strongest and followed in the bud opening and leaf spreading stages. The tolerance of new shoot growth stages was the weakest. 【Conclusion】 Research suggested that -7.70℃ is the turning point for severe frost at the pompom stage, while the critical temperature of bud opening stage was -4.49℃. The temperature lower than -2.79℃ at the leaf spreading stage bright irreversible damage to the wine grape. Furthermore, a low temperature below -1.62℃ in the new shoot growth stage caused severe frost.

Abstract:【Objective】 The aims of this article was to study effects of short-term warming, precipitation reduction on the species diversity, functional traits and productivity, reveal the responses of short-term warming, precipitation reduction on community characteristics to climate change in sandy grassland. 【Methods】 The authors investigated the combined effects of precipitation reduction (0%, 20%, 40%and 60%) and warming using open-top chambers (OTCs) on plant community composition, species diversity and functional trait and relationship between community characteristics and environmental factors. 【Results】 The important findings was: (1) Short-term warming, precipitation reduction led to changes in the plant community composition and species dominance of sandy grassland, dominant species of Artemisia scoparia, Lespedeza davurica and the community coverage, aboveground biomass was significantly lower. (2) The short-term warming significantly reduced Margalef richness index, Simpson index, Shannon index and Pielou index, but the short-term precipitation reduction had no significant effect on the four species diversities. (3)The short-term warming significantly increased the heightleaf dry matter content and reduced the leaf thickness, but the short-term precipitation reduction significantly increased the leaf dry matter content, leaf thickness and reduced the height, specific leaf are of plant community. (4) The short-term warming was affecting the species diversity and functional traits of the main environmental factors in sandy grassland. 【Conclusion】 In summary, Short-term warming, precipitation reduction changed community characteristics, temperature was affecting the community characteristics of the main environmental factors in sandy grassland.

Abstract:【Objective】 To analyze the population structure and dynamic characteristics in different habitats and explore the main influencing factors, so as to provide theoretical basis for the protection, restoration and renewal of the population in this area. 【Methods】 The static life table and the survival curve and the survival analysis function curve of the population were compiled by investigating the population of the dragon palm in three different habitats (broad-leaved forest, mixed forest and shrub) in Dajianshan Nature Reserve of Chuxiong, and the population dynamics were predicted by using the time series model. In order to understand the population structure and dynamic characteristics in different habitats. 【Results】 The results showed that in the three habitats, the population was in a state of decline, sensitive to external interference, the survival curve showed DeEVeY-III type, and a large number of individuals died in the seedling stage. In the three different habitats, the distribution of dragon palm population was uneven and clustered, indicating that the seed spread of Minglong palm was centered on the mother plant. 【Conclusion】 In terms of population density, the population density of dragon Brown was the highest in broad-leaved forest, followed by mixed forest, and the smallest was shrub. Combined with the study on the population age structure, it was further proved that the broad-leaved forest and the mixed forest with better water conditions were more conducive to the survival of the population.

Abstract:【Objective】 As for the aspect of species representativeness and diversity, the article aims to provide a scientific evidence for plant diversity conservation, plant resource utilization in Qinghai area of Kunlun Mountains National Park. 【Methods】 Based on field surveys, historical data and literature, sorted out the list of seed plants in the assessment area, and analyzed the composition, dominant taxa, geographic component and endangered species of seed flora were assessed in the area. 【Results】 The results showed that: (1) There was a total of 46 families, 146 genera and 383 species of seed plants in Qinghai area of the Kunlun Mountain National Park, including three families, three genera and five species of gymnosperms, and 43 families, 143 genera and 379 species of angiosperms; the four families including Amaranthaceae, Asteraceae, Fabaceae and Poaceae occupy an important position in the seed flora of the assessed area, and monospecie and oligospecie constitute the main part of the family. (2) The family and genus dominances of seed plants were obvious in this area with eight dominant families and 36 dominant genera, six large genera had more than 10 species including Astragalus, Oxytropis, Artemisia, Saussurea, Poa and Carex (3) The areal-type of the families in this seed flora was mainly cosmopolitan, meanwhile it showed a temperate nature, and the areal-type of genera was mainly temperate distribution with a close connection to the Laurasia. (4) There were four species of national Grade Ⅱ protected wild plants, eight species of Qinghai Province key protected plants, and six species listed in this area. 【Conclusion】 As a whole, the seed flora in Qinghai area of the Kunlun Mountains National Park was remarkably characterized by temperate nature and clear transitional property with low plant species richness, less endemic family, genus and species.

Abstract:【Objective】 The study aims to definite the karyotypic characteristics and genetic relationships of 12 species of Oxalis from a cytology of view, to provide a reference for exploring the chromosome diversity of Oxalis, identifying the germplasm resources of Oxalis, and selecting the parents for cross-breeding. 【Methods】 The chromosome morphology, number and karyotype of 12 species of Oxalis plants were observed and analyzed by applying the root-tip compression method. 【Results】 The results showed that: (1) Chromosome numbers are reported for the first time for seven species, and of the five reported species, O. fabaefolia and O. pes-caprae have chromosome numbers consistent with previous reports, while the remaining three, differ from previous reports, of which 2n=26 was the first reported chromosome number in the genus Oxalis. A total of seven chromosome bases were found, of which x=13 was reported for the first time; ploidy ranged from 2x to 6x, actual chromosome sizes ranged from 0.27 μm to 2.23 μm, and the location of the attachment point was the metacentric (m) and submetacentric (sm) chromosomes. There were four karyotype types and the karyotype asymmetry coefficients ranged from 56.31% to 65.40%. (2) Among them, O. fabaefolia was the most evolved, and O. compressa was the most primitive. (3) According to the similarity of chromosomal karyotypes, the 12 species of Oxalis can be divided into four groups. 【Conclusion】 It was concluded that the 12 species of Oxalis had extensive karyotypic diversity and that the results of the karyotypic classification were not in complete agreement with the morphological classifications of the previous researchers.

Abstract:【Objective】 Castanopsis grandicicatricata N. H. Xia & D. H. Vuong, a newly recorded species of Castanopsis (Fagaceae) from China is reported. This species is originally endemic to central and northern Vietnam, but now a scattered population is discovered in the Dawei Mountain area of Pingbian Miao Autonomous County, Yunnan. The study aims to verify the close relatives of the original literature based on morphological speculation, show the systematic status of this species, and increase the richness of Castanopsis plants in China. 【Methods】 The morphology-based speculation on the close relatives mentioned in the original literature was validated through phylogenetic tree reconstructions using nucleus ITS2 of rRNA gene 5.8S, 26S spacer and chloroplast rbcL molecular markers. 【Results】Morphologically, it can be distinguished from other known Castanopsis species by its cupule 4.5-6.0 cm in diameter, spine base connate into tree-like branched bundles, nut oblate, scar covering ca. 2/3 of the nut. 【Conclusion】 The results confirmed that C. mekongensis is indeed one of its close relatives, consistent with the morphological speculation; however, the overall phylogenetic framework of the genus is not clear. This new record holds significant implications for studying the flora of southeast Yunnan and northern Vietnam.