Abstract:In order to analyze the genetic differences and genetic background of natural hybrid progenies of tea, the molecular markers research was carried out based on 82 natural hybrid progenies of tea and 34 main cultivated varieties in Fujian by using 24 simple repeat sequence marks to analyze the genetic relationship, population genetic diversity and parental simulation analysis.The results indicate that (1) A total of 157 polymorphic sites were detected,with an average of 6.542 alleles,an average of 0.588 for nei''s diversity index and 1.182 for shannon information index,the mean values of observed and expected heterozygosity were 0.577 and 0.591,respectively. (2)The method of genetic distance clustered all the accessions into four groups, group one were mainly ‘Dangui’and the natural hybrid progenies of‘Dangui’, group two were mainly the Oolong tea varieties in Fujian and the natural hybrid progenies of ‘Dangui’,‘Huangguanyin’, group three were mainly‘Baijiguan’and the natural hybrid progenies of ‘Baijiguan’,group four were mainly the green tea varieties in Fujian. (3)The genetic distance between the natural hybrids of‘Dangui’,‘Baijiguan’,‘Huangguanyin’, and the main cultivar in Fujian were 0.079, 0.117 and 0.107 respectively.(4)The simulated parents were mainly the oolong tea variety in Fujian, the genetic identity, genetic differentiation index and gene flow between subgroup b of group one and subgroup a of Group two were 0.899、0.043 and 5.480 respectively.(5)AMOVA attributed about 88.52% of the variance to individuals within populations, indicating that the main genetic variation existed within populations.

Abstract:To explore the role of NAC transcription factors (TFs) in the progress of the retrieved green of Fe-deficiency chlorotic leaves in ‘Dangshansuli’ pear (Pyrus bretschneideri Rehd.), PbrNAC TFs were screened in the pear leaves, and the expression patterns of key PbrNACs in response to the retrieved green progress were analyzed. In this study, normal leaves (N) and chlorotic leaves (C) of ‘Dangshansuli’ pear were taken as test material, and exogenous 0.2% FeSO4 (2 g/L FeSO4) solution was sprayed on C during the growing season to confirm its effect and Fe2+ accumulation in C, with N and C treated with distilled water as the control (CN and CC). We have studied the biological properties, tissue-specific expression, and response patterns of the key PbrNAC in this progress. Moreover, the correlation analysis between the expression of PbrNAC with Fe2+ content was carried out. The results showed, (1) A total of 21 PbrNAC genes with typical NAM domain were significantly differently expressed between N and C, which could be clustered into 7 subclasses with fewer introns and with motifs ranging from 4 to 9. (2) Most of the PbrNAC genes preferred to express in the roots, and all the genes could respond to the retrieved green progress of C. Among them, the expression levels of the seven genes named Pbr032231.1/Pbr021393.1/Pbr026635.1/Pbr038615.1/Pbr019210.3/Pbr019212.1/Pbr002372.1 was significantly lower in CC than that in CN, and after FeSO4 treatment, their expression was significantly increased compared to that of CC; In contrast, the expression levels of 14 PbrNAC genes, including Pbr007284.1/Pbr016205.1/Pbr007673.1, were notably higher in CC than that in CN, and after FeSO4 treatment, they were more likely to increase with statistical differences. (4) The Fe2+ content in leaves was significantly negatively associated with the expression of Pbr007284.1/Pbr016205.1/Pbr007673.1. Although other NAC TFs did not show a direct linkage with the Fe2+ accumulation, there is a certain relationship between them and Pbr007284.1/Pbr016205.1/Pbr007673.1, such as Pbr016932.1/Pbr027956.1/Pbr029956.1/Pbr026635.1. (4) Consistent with the difference in the transcript level in aboveground leaves, the expression of Pbr007284.1/Pbr016205.1/Pbr007673.1 homologs in roots of normal pear trees were also prominently higher than that in roots of chlorotic pear trees, implying a synergistic regulatory effect. Overall, PbrNAC genes may be related to the retrieved green progress of CC, and may be involved in Fe deficiency response in pear, where Pbr007284.1, Pbr016205.1, and Pbr007673.1 might play a vital regulatory role.

Abstract:The aim of this study is to find out the reference genes stably expressed in various abiotic stresses of Haloxylon ammodendron, so as to lay a foundation for the subsequent study on the function of genes related to stress resistance of H. ammodendron. In this study, real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression changes of 14 candidate internal reference genes, including GAPDH, EF-1α, UBC, RPL32, ALB, 50S-1721, 50S-1063, RPⅡ, H3, PP2A, SOD, HSC70, TUA, and TUB, from the transcriptome database of H. ammodendron, under high temperature, drought, salt, abscisic acid (ABA) and circadian rhythms. By using geNorm, NormFinder, BestKeeper and RefFinder software, the stability of candidate internal reference genes of H. ammodendron was evaluated, and suitable internal reference genes were finally selected. Furthermore, the expression of phosphoenolpyruvate carboxylase (PEPC) gene was analyzed to verify the influence of different reference genes on the experimental results. And significant differences were found in the optimal internal reference genes analyzed by the four software programs, and the comprehensive ranking analysis on the RefFinder website showed that ALB was the optimal internal reference gene under ABA treatment and circadian rhythms, the RPⅡ gene was most stably expressed in leaves under drought stress, TUB and RPⅡ were most suitable internal reference genes under salt stress, and the H3 gene was most stably expressed under high temperature stress. The most suitable internal reference genes under all stresses were ALB and RPL32. By calculating the geometric mean, the comprehensive stability ranking of 14 candidate internal reference genes was obtained, of which the top two genes were SOD and RPL32, respectively. In conclusion, RPL32 and SOD can be used as internal reference genes for qRT-PCR standardization.

Abstract:In order to investigate the function of the potato HXK family, this study used bioinformatics to identify the members of the potato HXK gene family and real-time fluorescence quantitative PCR to analyze the expression of this gene under different simulated stresses of adversity. This study identified the potato HXK genes, named StHXK1-StHXK6, from the potato genome using the homology matching method. The family genes were distributed on six chromosomes of potato, and their encoded proteins ranged from 497 to 533 aa in length, with an isoelectric point of 5.36-6.11 and molecular masses ranging from 53 736.38 to 58 184.71 Da, all of which are hydrophilic proteins. Subcellular localization predictions indicate that members of the StHXK family are predominantly expressed in chloroplasts. The secondary structures of all members of this family are dominated by α-helices and irregular coiling, and the tertiary structures are highly similar. The promoter region of the StHXK family contains light-responsive elements, hormone-responsive elements, stress-responsive elements and growth and development-related elements. The qRT-PCR results showed that all StHXK genes were significantly up-regulated under ABA induction, and the relative expression of StHXK1 and StHXK2 was higher under 50 μmol/L ABA stress at 24 h of treatment, 286.4 and 152.02 times higher than that of the control, respectively. Under 200 mmol/L NaCl treatment, the relative expression of all StHXK genes was down-regulated except for StHXK1 and StHXK4 genes which were up-regulated at 2 h of treatment time. The relative expression of StHXK gene was differentially up-regulated under 10% PEG stress treatment. In summary, the StHXK gene responded to ABA, NaCl and PEG stress treatments to varying degrees.

Abstract:Fruit color is one of the important commercial traits of pepper. In this study, ornamental pepper GS6, Z1, sweet pepper SP01 and its yellow mutant SP02 were used as materials to explore the sequence differences and expression characteristics of capsanthin/capsanthin synthase (CCS) gene in pepper with different mature fruit colors, and to preliminarily analyze the molecular mechanism of pepper with different mature fruit colors. The results showed that the full-length CCS gene could be cloned from GS6, Z1 and SP01 with red mature color, and there was no difference in the sequence. The full-length of CCS gene was 1497 bp, encoding 498 amino acids, containing only one open reading frame sequence and no intron sequence. The CCS gene was not cloned in the yellow mutant SP02. Clustering and phylogenetic analysis showed that the CCS genes of Capsicum annuum were more closely related to Capsicum chinense, Capsicum baccatum, and Solanum pennellii of Solanaceae crops. The results of qRT-PCR analysis showed that the expression of CCS gene was the highest in flowers in GS6. In Z1 and SP01, the expression level of CCS gene in fruit was significantly higher than that in other tissues, and the expression level in root was the lowest. The CCS gene was not expressed in the stems and leaves of SP01 and all tissues of SP02. At different fruit development stages, the expression of CCS gene increased significantly at 30 days after flowering ( stage III ) of SP01, 40 days after flowering ( stage IV ) of GS6 and Z1. The results showed that the formation of fruit color of sweet pepper yellow mutant SP02 may be closely related to the deletion or variation of CCS gene, and the expression of CCS gene in mature red pepper may play an important role in fruit color formation.

Abstract:MYB transcription factors play a major regulatory role in plant anthocyanin biosynthesis. In order to explore the role of MYB transcription factor in the formation of the blue flower color of Muscari armeniacum，this study used M. armeniacum as the experimental material，based on the local deep mining of the transcriptome database of the research group, and cloned one R2R3-MYB gene named MaMYB114 (GenBank accession number：OQ615377). For bioinformatics analysis and functional validation of heterologous transformed tobacco. The results showed that：(1) The open reading frame of MaMYB114 has a total length of 714b p，encoding a protein of 425 amino acids；Sequence alignment showed MaMYB114 protein contains the R2R3 conserved domain，indicating that it belongs to the AN2 subfamily of the R2R3-MYB family. (2) The results of subcellular localization and transcriptional self-activation confirmed that MaMYB114 was located in the nucleus and had transcriptional autoactivation activity，which was consistent with the general characteristics of transcription factors. (3) Real-time quantitative PCR analysis showed that MaMYB114 gene was highly expressed mainly in flowers，and the expression pattern was tissue-specific. Combined with the change patterns of anthocyanin content at different times，it was found that MaMYB114 was highly expressed in flower buds with high anthocyanin content during the coloring stage，indicating that MaMYB114 participated in the synthesis process of anthocyanins in grape hyacinths. (4) Overexpression of MaMYB114 promotes anthocyanins accumulation in tobacco, indicating that MaMYB114 positively regulates anthocyanin synthesis. This study indicates that the MaMYB114 gene may be an important regulatory gene involved in the formation of the blue color of grape hyacinth.

Abstract:To provide a theoretical basis for revealing the relationship between ultraweak luminescence (UWL) and plant growth physiology and the source of UWL production in plants. In this experiment, Cerasus humilis was used as the test material and conducted an indoor potted experiment with different concentrations of salt stress treatment to study the change rule and correlation of chloroplast structure and function (chlorophyll metabolism, photosystem activity, photosynthetic performance and energy level) and UWL of Cerasus humilis leaves under salt stress. Results show that: (1) salt stress reduced the UWL intensity of Cerasus humilis leaves, and the higher the salt concentration, the greater the decrease in UWL strength. (2) Salt stress destroyed the chloroplast structure of Cerasus humilis leaf and reduced its function. The decrease in chloroplast function includes a significant decrease in the content of the main precursor substances for chlorophyll synthesis (ALA, Mg-ProtoⅨ),, and the activity of chlorophyll-degrading enzyme chlorophyll enzyme (Chlase) significant increased, resulting in a significant decrease in chlorophyll congtent (Chla, Chlb, Car and Chla+b). At the same time, the FV/Fm, FV/FO, PIABS, RC/CSm, φE0 and ΨE0 of the leaves of Cerasus humilis decreased rapidly, and the activity of photosystem II was severely inhibited. Make further decrease on the Pn, Tr, and Gs, while Ci increase simultaneously, resulting in a significant decrease in photosynthetic performance. The significant decrease in ATP content and EC lead to an overall decrease in energy levels. (3) UWL intensity of Cerasus humilis leaves and their chlorophyll synthesis precursors and chlorophyll content (ALA、Mg-ProtoⅨ、Chla、Chlb、Car and Chla+b), photosystem II activity (FV/Fm、FV/FO、PIABS、RC/CSm、φE0、ΨE0), photosynthetic performance (Pn、Tr、Gs) and energy level (ATP、EC) all showed significant or extremely significant positive correlations. (4) The higher the salt concentration, the longer the stress time, and the greater the degree of changes in the UWL intensity and chloroplast function indicators of Cerasus humilis leaves, and the overall correlation under high-concentration salt treatment is higher than that under low-concentration salt treatment. In summary, under salt stress conditions, the chloroplast structure of Cerasus humilis leaves is destroyed, while its function is damaged and its vitality decreases, resulting in a decrease in UWL intensity. The intensity of UWL is closely related to chloroplasts and their functions, and chloroplasts may be one of the organelles of UWL. The UWL intensity can be used to reflect the degree of salt stress damage to the leaves of Cerasus humilis.

Abstract:In order to explore the effects of S-ABA, methyl jasmonate (MeJA), and coronarin (COR) plant growth regulators on the color and quality of ‘Flame Seedless’ grapes, and to screen out the best measure to promote the coloration and quality of ‘Flame Seedless’ grapes. Three treatments of 100 mg/L S-ABA, 60 mg/L MeJA, and 2000 times dilution of COR were set up, and the ears were dipped at the early stage of color change and sampled seven times from the treatment to the mature stage. The berry weight, longitudinal and transverse diameter, and the contents of soluble solids, total acid, anthocyanin, chlorophyll, carotenoids, and phenolic compounds were measured and analyzed continuously. The results showed that (1) S-ABA, MeJA, and COR treatments could promote fruit coloration, significantly increase the fruit surface color parameter a* value, and decrease the L* value, b* value, and h°; The contents of anthocyanin in the three treatments were significantly increased by 62.84%, 58.72%, and 23.98%, respectively. (2) S-ABA, MeJA, and COR treatments could improve fruit quality. Compared with the control, the soluble solids content increased by 9.17%, 7.45%, and 9.74%, the total acid content decreased by 6.81%, 4.14%, and 9.25%, and the soluble solids to total acid ratio increased by 17.90%, 12.16%, and 20.82%, respectively. (3) S-ABA, MeJA, and COR treatments increased the berry weight, longitudinal diameter, and transverse diameter, increased flavonoids, flavonoid, flavanols, and total phenols content, and decreased total acid and tannins content, but had no effect on fruit shape index and pedicel endurable pulling force. (4) Anthocyanin content was positively correlated with soluble solid content, a* value and CIRG value (P<0.05), but negatively correlated with h°, L* value, b* value, total acid content and chlorophyll content; It was negatively correlated with L* value, b* value, h° and total acid content.; the anthocyanin content was positively correlated with total phenols content, but negatively correlated with flavonoids content, flavanols content, and flavonoid content. The results showed that 100 mg/L S-ABA and 2000 times dilution in the early stage of color transformation could effectively promote the color of ‘flame seedless’ grapes and improve fruit quality. The a* value and CIRG value of fruit color were positively correlated with anthocyanin content (0.80, 0.70), which could be used as a reference index for quantifying fruit coloration.

Abstract:IIn order to investigate the quality difference of ash jujube under different drying conditions, screen suitable drying temperature and time, and provide basic theoretical data and technical reference for hot air drying of ash jujube, postharcrop ash jujube was used as test material in this study. The appearance quality and internal quality of jujube were measured under different drying temperature (45 ℃, 55 ℃, 65 ℃, 75 ℃) and different drying time (4 h, 6 h, 8 h), and the quality of dried fruit was evaluated comprehensively. The results show that: (1) Under treatment at 45 ℃, 55 ℃ and 65 ℃ for 4-6 h, the skin color was brighter, the internal Browning was not obvious, the sensory evaluation score was higher, and the vertical and horizontal diameter of the fruit was little affected. However, with the increase of drying temperature and the extension of drying time, the skin color of the fruit gradually changed from bright to dark, and the red color faded. The yellow color becomes darker and crease obviously, the internal Browning is more serious, and the taste and flavor become worse. (2) The contents of dried flavonoids, total phenols, soluble sugars and titrable acids were higher under the conditions of continuous treatment at 65 ℃ and 75 ℃ for 6-8 h, but the lower epidermal color, internal non-browning, sensory evaluation and fruit shape index were poor under the conditions of 65 ℃/8 h, 75 ℃/6 h and 75 ℃/8 h. (3) The best drying temperature and time of postharvest ash date was 45 ℃/4 h through principal component analysis.

Abstract:Salt stress is the main type of abiotic stress affecting crop growth, causing ion toxicity and osmotic stress, leading to weakened plant growth, greening, wilting and even death. Previous studies have shown that the appropriate concentration of exogenous spermidine can alleviate the damage degree of plant leaves under salt stress conditions, enhance the ability of biofilm to resist salt ion damage, and promote plant growth. The experiment adopted nutrient solution culture method to simulate different salt stress levels with 100mmol·L-1, 200mmol·L-1 and 300mmol·L-1 NaCl solutions. And the medium salt-tolerant variety Jinshu 16 and the mild salt-tolerant variety Jizhangshu 12 were used as test materials. When the virus-free potato seedlings reach 4~5 true leaves, continuous foliar spraying of 0.9 mmol·L-1 exogenous spermidine was applied for 7 day, 2 times per day. The effects of exogenous spermidine (Spd) on the growth of potato seedlings, the activity of antioxidant enzymes and the content of osmotic regulatory substances in leaves were analyzed. The results showed that: (1) Leaf spraying Spd alleviated the inhibitory effect of salt stress on seedling growth, increased chlorophyll content and root activity, and increased the activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), ascorbate (ASA) and glutathione (GSH). And proline, soluble sugar, amino acid content; (2) Under 200 mmol· L-1NaCl stress, Spd had the most significant alleviating effect on "Jinshu 16". Studies have shown that Spd can improve the adaptability of potato seedlings to salt stress and promote the growth of potato seedlings by improving the root vitality, chlorophyll content, antioxidant enzyme activity and osmotic regulation ability of potato seedlings.

Abstract:To explore the effects with different temperature on the dormancy regulation of konjac bulbil, the foliar bulbils were used as the material. The day/night temperature (24 ℃/9 ℃, 24 ℃/13 ℃, 24 ℃/17 ℃) and constant temperature (9℃, 13℃, 17℃, 21℃) were set during the dormancy period, and the temperature was set at 26 ℃ and 33℃ during the germination period. Analyzed the biological phenotypic changes, endogenous physiological changes and expression of genes related to dormancy regulation after different temperature treatment in dormancy Ⅰ , Ⅱ , early germination , germination of mid , germination of late and terminal germination stage. The results show that (1) Constant temperature treatment during the dormancy stage was beneficial to improve the budding ratio of konjac bulbil. Dormancy was broken by constant temperature treatment at 13℃ in the dormancy stage, and germination rate of konjac bulbil reached its peak at 33℃ in the germination stage. (2) The content of starch in bulbil at dormancy Ⅱ stage was lower than dormancy Ⅰ stage, the content of soluble sugar in bulbils at dormancy Ⅱ stage was higher than dormancy Ⅰ stage, the content of starch in bulbils at 13℃ decreased the fastest, and the content of soluble sugar in bulbils at 13℃ was the highest. There were significant differences in starch content and the soluble sugar content of bulbils between early and late stage of germination (P < 0.05) .(3) The content of ABA in bulbils increased gradually, and the content of GA3 decreased gradually in dormancy stage Ⅰ and dormancy stage Ⅱ. The ABA content of bulbils in germination period showed a trend of "first rising and then decreasing" and the content of GA3 in bulbils treated at 26℃ also showed the same trend in germination period. The GA3 content of bulbils treated with a germination temperature of 33℃ showed an overall upward trend. (4) The expression level of NCED gene increased gradually with the deepening of dormancy and decreased gradually during germination; The expression of CYP707A gene decreased gradually with the deepening of dormancy and increased significantly during germination.In conclusion,we found that the optimal temperature for breaking dormancy was 13℃, and the optimal temperature for promoting germination was 33℃. As the konjac bulbil broken the dormancy, the starch content in the bulbils decreased and the soluble sugar content increased; ABA content showed a trend of "first rising and then decreasing", GA3 content showed a trend of "first decreaseing and then rising"; and we suggest that the gene NCED and CYP707A may be the key genes in the dormancy regulation of konjac bulbil.

Abstract:The rules of nutrient absorption and its relationship with the accumulation of medicinal composition were studied , in order to clarify the types of nutrient elements that affect the accumulation of medicinal components and provide a theoretical basis for the scientific formulation of fertilization plans and standardized planting of Paeonia lactiflora in the Hexi region. The 4-year-old Paeonia lactiflora were taken as the research material in in Gufeng Town, Gulang County, Gansu Province ,the dry matter accumulation characteristics, nine nutrient elements and three types of medicinal composition of Paeonia lactiflora at different growth stages were studied, and the correlation between the content of effective components in Paeonia lactiflora and nutrient elements was explored with field experiments. The results showed that the accumulation of dry matter in the roots of Paeonia lactiflora showed a trend of first decreasing and then increasing. The dry matter of the entire plant of Paeonia lactiflora gradually increases with the growth period, and the period of 90 to 130 days after emergence is the fastest period for dry matter accumulation , accounting for 79.29% of the total accumulation. It was a critical period for the growth of Paeonia lactiflora. The nitrogen and potassium content showed decreasing trend, while the phosphorus content showed significant increasing trend in the aboveground parts of Paeonia lactiflora at different growth stages. The nitrogen and phosphorus content showed decreasing trend in the roots, while the potassium content changed little. The total accumulation of aboveground and root nitrogen reached their highest levels at 130 and 150 days after emergence, respectively .The accumulation of aboveground phosphorus reached its maximum at 150 days, while the accumulation of root phosphorus reached its peak at 30 and 150 days after emergence. The accumulation of aboveground potassium reached its maximum at 70 days and the accumulation of root potassium reached its peak at 150 days after emergence. The nitrogen and potassium contents in the aboveground parts were higher than those in the roots at different growth stages, while the phosphorus content was lower than the roots before 90 days and higher than the roots after 110 days after emergence. The accumulation of paeoniflorin and albiflorin in roots first increased, then decreased, and finally stabilized. The accumulation of polysaccharides showed a trend of high low high.The content of paeoniflorin is highly significantly positively correlated with nitrogen, calcium, and copper content, and significantly positively correlated with potassium content. The content of albiflorin is highly significantly positively correlated with nitrogen, potassium, calcium, and copper content, while there is no correlation between polysaccharide and various nutrients.The maximum efficiency period of nitrogen, phosphorus, and potassium nutrition was 110-150 days after emergence. Nitrogen and potassium fertilizers was beneficial for the accumulation of root biomass. Adding Ca and Cu elements to fertilization could effectively promote the accumulation of effective components in Paeonia lactiflora. Paeonia lactiflora should be harvested in the cold and cool mountainous areas of Hexi in mid to late September (after September 16th).

Abstract:Selaginellaceae is a monotypic lycophyte family. The genus Selaginella contains about 700 extant species distributed all over the world. Selaginellaceae originated in the Devonian period, and the fossil record covers various geological periods from the Carboniferous period to the present. Several infrageneric systems of modern Selaginella have been proposed, however, research on the classification and geological history of Selaginellaceae fossils is still lacking. In the present review, time and geographical distribution of the fossil records were summarized, and the evolution and formation of the geographical distribution pattern were discussed in combination with molecular systematic studies, providing a reference for the taxonomic and evolution studies of Selaginella. Based on the latest taxonomy and the fossil records, we summarized and determined the systematic taxonomy of fossils, and discussed the differentiation and geographical distribution of subgenus Selaginella, subgenus Hexaphyllum and the rhizophoric clade. We concluded that Selaginellaceae originated in the Paleozoic Euramerican floral realm not later than the Permian, and spread to the Cathaysian and Gondwana floral realms along with the splitting of Pangea. The fossil subgenus Hexaphyllum is the basal group of the rhizophoric clade, which became extinct at the end of the Carboniferous. Fossil evidence shows that since the end of the Paleozoic, the rhizophoric clade might have become the dominant group of Selaginellaceae, and formed a global distribution pattern in the Mesozoic.

Abstract:In order to clarify the ion distribution, absorption and transport laws of P. euphratica, and to explore the physiological mechanism of P. euphratica"s adaptation to the saline environment, P. euphratica was used as the research object to determine the soluble salt ion content in the roots, trunks, old branches, young shoots and leaves, and study the uptake, transport and distribution characteristics of each ion, combined with the salt characteristics of understory soil. The relationship between P. euphratica ion distribution and soil salinity was discussed, and the results showed that:With the changes of leaf-unfolding phenology, P. euphratica meets the needs of growth and development as well as the adaptation to the environment through the difference of ion absorption, transportation and distribution rules. (1) The ability of selective absorption of K+, Ca2+ and Mg2+ by roots increased firstly and then decreased with the changes of leaf-unfolding phenology, and most of them were in the rapid leaf development stage as the highest, which was just the opposite to the change trends of total salt and Na+ and Cl- contents in soil. (2) With the changes of leaf-unfolding phenology, the transportation capacity of ions from root to trunk and juvenile branch to leaf presented the opposite trend of first decline and then rise, and most of them were in the rapid development period of leaf as the lowest. (3) Na+ and K+ contents in different organs changed little during the leaf developing process but increased significantly during the leaf mature period, in which the content of Na+ in root was the highest and that of K+ in leaf was the highest. The contents of Ca2+ and Mg2+ in leaves and roots generally increased with the changes of leaf-unfolding phenology. (4) The correlation between organ ions and soil ions of P. euphratica in the leaf-unfolding phenophase is as follows: In the germination stage, the ion content of each organ is less affected by soil salt, and the correlation between indicators is mostly insignificant; During the leaf-unfolding stage, Na+ in roots positively correlated with soil ions, while K+ in young branches and main stems negatively correlated with soil ions. During the rapid development of leaves, Mg2+ in young branches and Na+ in roots were positively correlated with soil ions. The ion content of each organ was less affected by soil ions during the leaf mature period.

Abstract:In 2021, following the establishment of the Hainan Tropical Rainforest National Park, specific sectors of the artificially managed woodlands within the park ceased operational activities, entering a state of secondary natural succession. This shift has given rise to a more profuse understory vegetation compared to prior years, necessitating further exploration. To gain insights into the secondary natural succession status of the artificial forests and their adaptive strategies to the environment, a study was executed in the rubber tree plantation within the Hainan Tropical Rainforest Park. A total of 390 plots, each measuring 10 m × 10 m, were instituted. Expanding upon a comprehensive survey of vegetation distribution within the Hainan Island park, the research focused on scrutinizing the composition of understory vegetation and the correlation between plant community characteristics and environmental factors in the designated area. The findings disclosed that: Vascular plants were systematically categorized into 123 families, 455 genera, and 808 species. This comprises 21 families, 31 genera, and 62 species of ferns, 3 families, 3 genera, and 4 species of gymnosperms, and 99 families, 421 genera, and 742 species of angiosperms (encompassing 15 families, 69 genera, and 120 species of monocots, and 84 families, 352 genera, and 622 species of dicots). Redundancy analysis (RDA) of plant species diversity indices and environmental factors in the study area illuminated 18.5% of the variability in species diversity beneath the rubber tree canopy. Monte Carlo random permutation tests identified eight environmental factors significantly influencing understory species diversity in the rubber tree plantation (P<0.05), with the most salient effects observed for the average temperature in the driest quarter, average temperature in the wettest quarter, mean diurnal temperature range, and the influences of mixed vegetation, diameter at breast height (DBH), elevation, annual precipitation, and precipitation in the driest quarter (P<0.01). The study posits that understory plant diversity is subject to the interactive effects of multiple environmental factors. Specifically, temperature and precipitation emerge as pivotal factors influencing understory plant diversity, with adverse impacts observed under conditions of heightened temperature, increased humidity, and drought. Additionally, altitude-related thermic conditions and the condition of artificial forests, including DBH and mixed vegetation, assume noteworthy roles in shaping understory plant diversity.

Abstract:The craters of Jingpo Lake World Geopark breed rare primitive underground forests. This study provides important data for improving the origin of bryophyte floristic geography of volcanic ecosystem in China. Based on previous field surveys, specimen collection and species identification, it is known that there are 53 families, 126 genera, and 292 species of bryophytes.The methods of hierarchical cluster analysis and principal component analysis were used for exploring the floristic geographical characteristics of bryophytes. The results show that: (1) The monotypic and oligotypic genera of bryophytes were dominant in the underground forests in the craters of Jingpo Lake World Geopark, with a total of 106 genera (accounting for 84.13% of the total genera) and 152 species (accounting for 52.05% of the total species). (2) There were 11 floristic geographical components, of which the north temperate was the dominate component (49.12%), followed by East Asia (21.55%), and the third was Endemic to China (8.48%). (3) Endemic to China bryophytes in underground forests may spread along the "North line" through mountain ranges. (4) The similarity of bryophytes flora was the highest between underground forests in cratersof Jingpo Lake and volcanic lava platform of Jingpo Lake. Additionally, seven threatened bryophytes were discovered. In short, the main characteristics of the bryophytes flora of underground forests in the craters of Jingpo Lake were ancient origin, complex composition, significant north temperate properties, and had a profound historical origin with the East Asia. It was a refuge for Endemic to China, rare and endangered bryophytes attribute to the superior microhabitat inside the volcanic cones.

Abstract:Betalain is a kind of natural plant pigment mainly exists in Caryophyllales. It can be divided into betacyanins and betaxanthins. Betalain not only has the function of attracting insects for pollination, but also can act as an important osmoregulation substance and non-enzymatic antioxidant to help plants to defense against various biotic and abiotic stress cues and maintain normal physiological activities. Betalain has unique biosynthetic pathway and important medical and health value, and has been widely used in food, medicine and cosmetics. Combining with the latest research progress at home and abroad, this paper introduced the betalain from the aspects of physical and chemical properties, biosynthetic pathway, biological functions and application value, especially focused on the relationship between betalain and anthocyanin and the effects of light on betalain biosynthesis, so as to provide reference for further understanding and utilization of betalain.