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  • Profiling soil free-living nematodes in the Namib  Desert, Namibia

    分类: 生物学 >> 植物学 >> 应用植物学 提交时间: 2020-05-31 合作期刊: 《干旱区科学》

    摘要: Functional structure and diversity of soil free-living nematodes in a desert environment depend on plant gender and sampling site. The objective of this study was to compare the composition, abundance and tropic group of soil free-living nematodes in the upper 0–10 cm soil layer under the male and female Acanthosicyos horridus Welw. ex Hook. f. plants and in the inter-shrub open areas (control) in the Namib Desert, Namibia in April 2015. Soil moisture, organic matter (OM) and pH was also analyzed. Free-living nematodes were extracted from 100 g soil using the Baermann funnel procedure, and total number of nematodes was counted under a microscope. Community composition and diversity of soil free-living nematodes were analyzed using 18S rDNA sequences. Results indicated that a total of 67 groups, including 64 species, 2 genera and 1 family were identified. Feeding behavior of 58 species were identified as follows: 15 bacteria-feeding species, 12 fungi-feeding species, 10 plant-parasite species, 5 omnivorous-predator species, 8 animal-parasite species, 5 invertebrate-parasite species and 3 non-free-living nematodes, known as marine species. Moreover, soil free-living nematodes were found to be affected by sampling locations and plant gender, and community composition and density of these nematodes were strongly influenced by soil OM content. Result confirmed that spatial location and plant cover were main factors influencing the diversity of soil free-living nematodes. Moreover, molecular tools were found to be very useful in defining the richness of soil non-free-living nematodes. In conclusion, the results elucidated the importance of biotic variables in determining the composition and abundance of soil free-living nematodes in the Namib Desert, Namibia.

  • Profiling soil free-living nematodes in the Namib Desert, Namibia

    分类: 环境科学技术及资源科学技术 >> 环境科学技术基础学科 提交时间: 2020-04-23 合作期刊: 《干旱区科学》

    摘要: Functional structure and diversity of soil free-living nematodes in a desert environment depend on plant gender and sampling site. The objective of this study was to compare the composition, abundance and tropic group of soil free-living nematodes in the upper 0–10 cm soil layer under the male and female Acanthosicyos horridus Welw. ex Hook. f. plants and in the inter-shrub open areas (control) in the Namib Desert, Namibia in April 2015. Soil moisture, organic matter (OM) and pH was also analyzed. Free-living nematodes were extracted from 100 g soil using the Baermann funnel procedure, and total number of nematodes was counted under a microscope. Community composition and diversity of soil free-living nematodes were analyzed using 18S rDNA sequences. Results indicated that a total of 67 groups, including 64 species, 2 genera and 1 family were identified. Feeding behavior of 58 species were identified as follows: 15 bacteria-feeding species, 12 fungi-feeding species, 10 plant-parasite species, 5 omnivorous-predator species, 8 animal-parasite species, 5 invertebrate-parasite species and 3 non-free-living nematodes, known as marine species. Moreover, soil free-living nematodes were found to be affected by sampling locations and plant gender, and community composition and density of these nematodes were strongly influenced by soil OM content. Result confirmed that spatial location and plant cover were main factors influencing the diversity of soil free-living nematodes. Moreover, molecular tools were found to be very useful in defining the richness of soil non-free-living nematodes. In conclusion, the results elucidated the importance of biotic variables in determining the composition and abundance of soil free-living nematodes in the Namib Desert, Namibia.

  • Responses of plant diversity and soil microorganism diversity to nitrogen addition in the desert steppe, China

    分类: 生物学 >> 生态学 提交时间: 2024-03-13 合作期刊: 《干旱区科学》

    摘要: Nitrogen (N) deposition is a significant aspect of global change and poses a threat to terrestrial biodiversity. The impact of plant-soil microbe relationships to N deposition has recently attracted considerable attention. Soil microorganisms have been proven to provide nutrients for specific plant growth, especially in nutrient-poor desert steppe ecosystems. However, the effects of N deposition on plant-soil microbial community interactions in such ecosystems remain poorly understood. To investigate these effects, we conducted a 6-year N-addition field experiment in a Stipa breviflora Griseb. desert steppe in Inner Mongolia Autonomous Region, China. Four N treatment levels (N0, N30, N50, and N100, corresponding to 0, 30, 50, and 100 kg N/(hm2•a), respectively) were applied to simulate atmospheric N deposition. The results showed that N deposition did not significantly affect the aboveground biomass of desert steppe plants. N deposition did not significantly reduce the alfa-diversity of plant and microbial communities in the desert steppe, and low and mediate N additions (N30 and N50) had a promoting effect on them. The variation pattern of plant Shannon index was consistent with that of the soil bacterial Chao1 index. N deposition significantly affected the beta-diversity of plants and soil bacteria, but did not significantly affect fungal communities. In conclusion, N deposition led to co-evolution between desert steppe plants and soil bacterial communities, while fungal communities exhibited strong stability and did not undergo significant changes. These findings help clarify atmospheric N deposition effects on the ecological health and function of the desert steppe.

  • Transformation of vegetative cover on the Ustyurt Plateau of Central Asia as a consequence of the Aral Sea shrinkage

    分类: 地球科学 >> 地理学 提交时间: 2021-01-22 合作期刊: 《干旱区科学》

    摘要: The gradual shrinkage of the Aral Sea has led to not only the degradation of the unique environments of the Aral Sea, but also numerous and fast developing succession processes in the neighborhood habitats surrounding the sea. In this study, we investigated the vegetative succession processes related to the Aral Sea shrinkage in the Eastern Cliff of the Ustyurt Plateau in Republic of Uzbekistan, Central Asia. We compared the results of our current investigation (2010–2017) on vegetative communities with the geobotany data collected during the 1970s (1970–1980). The results showed great changes in the mesophytic plant communities and habitat aridization as a result of the drop in the underground water level, which decreased atmospheric humidity and increased the salt content of the soil caused by the shrinkage of the Aral Sea. In the vegetative communities, we observed a decrease in the Margalef index (DMg), which had a positive correlation with the poly-dominance index (I-D). The main indications of the plant communities' transformation were the loss of the weak species, the appearance of new communities with low species diversity, the stabilization of the projective cover of former resistant communities, as well as the appearance of a new competitive species, which occupy new habitats.

  • Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau, China

    分类: 农、林、牧、渔 >> 土壤学 提交时间: 2023-10-17 合作期刊: 《干旱区科学》

    摘要: Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties. However, plant composition and species diversity change rapidly during the process of succession, the effect of leguminosae on soil physical-chemical and biological properties is still unclear. This study investigated the changes in the composition of plant community, vegetation characteristics, soil physical-chemical properties, and soil biological properties on five former farmlands in China, which had been abandoned for 0, 5, 10, 18, and 30 a. Results showed that, with successional time, plant community developed from annual plants to perennial plants, the importance of Leguminosae and Asteraceae significantly increased and decreased, respectively, and the importance of grass increased and then decreased, having a maximum value after 5 a of abandonment. Plant diversity indices increased with successional time, and vegetation coverage and above- and below-ground biomass increased significantly with successional time after 5 a of abandonment. Compared with farmland, 30 a of abandonment significantly increased soil nutrient content, but total and available phosphorus decreased with successional time. Changes in plant community composition and vegetation characteristics not only change soil properties and improve soil physical-chemical properties, but also regulate soil biological activity, thus affecting soil nutrient cycling. Among these, Leguminosae have the greatest influence on soil properties, and their importance values and community composition are significantly correlated with soil properties. Therefore, this research provides more scientific guidance for selecting plant species to stabilize soil ecosystem of farmland to grassland in the Loess Plateau, China.

  • The production of human glucocerebrosidase in glyco‐engineered Nicotiana benthamiana plants

    分类: 生物学 >> 植物学 >> 应用植物学 提交时间: 2016-05-04

    摘要: For the production of therapeutic proteins in plants, the presence of 1,2-xylose and core 1,3-fucose on plants N-glycan structures has been debated for their antigenic activity. In this study, RNA interference (RNAi) technology was used to down-regulate the endogenous N-acetylglucosaminyltransferase I (GNTI) expression in Nicotiana benthamiana. One glyco-engineered line (NbGNTI-RNAi) showed a strong reduction of plant-specific N-glycans, with the result that as much as 90.9% of the total N-glycans were of high-mannose type. Therefore, this NbGNTI-RNAi would be a promising system for the production of therapeutic glycoproteins in plants. The NbGNTI-RNAi plant was cross-pollinated with transgenic N.benthamiana expressing human glucocerebrosidase (GC). The recombinant GC, which has been used for enzyme replacement therapy in patients with Gaucher's disease, requires terminal mannose for its therapeutic efficacy. The N-glycan structures that were presented on all of the four occupied N-glycosylation sites of recombinant GC in NbGNTI-RNAi plants (GCgnt1) showed that the majority (ranging from 73.3% up to 85.5%) of the N-glycans had mannose-type structures lacking potential immunogenic 1,2-xylose and 1,3-fucose epitopes. Moreover, GCgnt1 could be taken up into the macrophage cells via mannose receptors, and distributed and taken up into the liver and spleen, the target organs in the treatment of Gaucher's disease. Notably, the NbGNTI-RNAi line, producing GC, was stable and the NbGNTI-RNAi plants were viable and did not show any obvious phenotype. Therefore, it would provide a robust tool for the production of GC with customized N-glycan structures.

  • Research on the Innovative Development of Maonan Traditional Craft from the perspective of cultural Confidence

    分类: 工程与技术科学 >> 工程与技术科学其他学科 提交时间: 2023-01-10 合作期刊: 《Art & Design Research》

    摘要: Cultural confidence is one of the important factors to promote the inheritance and development of excellent national culture. Maonan traditional craft contains excellent national culture, cultural customs and so on, which is a part of carrying forward China's traditional culture confidence. From the perspective of cultural confidence, this paper analyzes the characteristics and advantages of the current Maonan traditional crafts and puts forward suggestions to promote the innovative development of Maonan traditional crafts, which can better promote the inheritance and development of Maonan traditional crafts.

  • Research on the Innovative Development of Maonan Traditional Craft from the perspective of cultural Confidence

    分类: 其他 >> 综合 提交时间: 2023-01-02 合作期刊: 《Art & Design Research》

    摘要: Cultural confidence is one of the important factors to promote the inheritance and development of excellent national culture. Maonan traditional craft contains excellent national culture, cultural customs and so on, which is a part of carrying forward China's traditional culture confidence. From the perspective of cultural confidence, this paper analyzes the characteristics and advantages of the current Maonan traditional crafts and puts forward suggestions to promote the innovative development of Maonan traditional crafts, which can better promote the inheritance and development of Maonan traditional crafts.

  • Do aeolian deposits and sand encroachment intensity shape patterns of vegetation diversity and plant functional traits in desert pavements?

    分类: 地球科学 >> 地理学 提交时间: 2023-06-13 合作期刊: 《干旱区科学》

    摘要:The effects of sand encroachment on composition, diversity, and functional patterns of vegetation in drylands are rarely studied, and yet addressing these aspects is important to deepen our understanding of the biodiversity conservation. This study aimed to investigate the effect of sand encroachment on plant functional biodiversity of desert pavements (gravel deserts) in the Sahara Desert of Algeria. Plants were sampled and analyzed in three desert pavements with different levels of sand encroachment (LSE) and quantity of aeolian deposits (low, LLSE; medium, MLSE; and high, HLSE). Within the sample-plot area (100 m²), density of every plant species was identified and total vegetation cover was determined. Plant taxonomic and functional diversity were analyzed and compared between LSE. Result showed that 19 plant species in desert pavements were classified into 18 genera and 13 families. Asteraceae and Poaceae were the most important families. The species Anabasis articulata (Forssk) Moq. characterized LLSE desert pavements with 11 species, whereas Thymelaea microphylla Coss. & Durieu ex Meisn. and Calobota saharae (C&D) Boatwr. & van Wyk were dominant species of desert pavements with MLSE (14 species) and HLSE (10 species), respectively. The highest values of species richness and biodiversity were recorded in desert pavements with MLSE, while low values of these ecological parameters were obtained in desert pavements with HLSE. Desert pavements with LLSE were characterized with the highest values of species abundances. Plant communities were dominated by chamaephytes, anemochorous, arido-active, and competitive stress-tolerant plants. The increase in LSE along the gradient from LLSE to HLSE induced significant changes in plant community variables including decreases in plant density, plant rarity, lifeform composition, morphological type, and aridity adaptation. Desert pavements with HLSE favor the degradation of vegetation and trigger biodiversity erosion.

  • Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert, Northwest China

    分类: 生物学 >> 植物学 提交时间: 2024-05-15 合作期刊: 《干旱区科学》

    摘要: Phyllosphere microorganisms are a crucial component of environmental microorganisms, highly influenced by host characteristics, and play a significant role in plant health and productivity. Nonetheless, the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains ambiguous. Utilizing high-throughput sequencing technology, this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms (e.g., bacteria and fungi) of various plant life forms in the hinterland of the Gurbantunggut Desert, Northwest China. Functional annotation of prokaryotic taxa (FAPROTAX) and fungi function guild (FUNGuild) were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial communities. Result showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants, with Proteobacteria, Cyanobacteria, and Actinobacteriota dominating bacterial community, while Ascomycota and Basidiomycota were prevalent in fungal community. Comparison across different plant life forms highlighted distinct microbial communities, indicating strong filtering effects by plant characteristics. FAPROTAX prediction identified intracellular parasites (accounting for 27.44% of bacterial community abundance), chemoheterotrophy (10.12%), and phototrophy (17.41%) as the main functions of epiphytic bacteria on leaves of different life form plants. FUNGuild prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs (81.77%), Pathotrophs (17.41%), and Symbiotrophs (0.82%). Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial taxa. Raup-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community assembly. Variance partitioning analysis and random forest modeling suggested that plant leaf functional traits significantly impacted both bacterial and fungal community composition, with fungal community composition showing a closer association with leaf nutrients and physiology compared with bacterial community composition. The distinct responses of bacterial and fungal communities to plant traits were attributed to the differing properties of bacteria and fungi, such as bacteria having higher potential dispersal rates and broader ecological niches than fungi. Overall, the results indicate that phyllosphere bacterial and fungal communities undergo similar community assembly processes, with fungi being more influenced by plant characteristics than bacteria. These findings offer novel insights into the ecology of phyllosphere microbial communities of desert plants.

  • Diversity of cultivable endophytic bacteria associated with halophytes in Xinjiang of China and their plant beneficial traits

    分类: 地球科学 >> 地理学 提交时间: 2021-09-08 合作期刊: 《干旱区科学》

    摘要: Endophytic bacteria from halophytes have a wide range of application prospects in various fields, such as plant growth-promoting, biocontrol activity and stress resistance. The current study aimed to identify cultivable endophytic bacteria associated with halophytes grown in the salt-affected soil in Xinjiang Uygur Autonomous Region, China and to evaluate their plant beneficial traits and enzyme-producing activity. Endophytic bacteria were isolated from Reaumuria soongorica (PalL Maxim.), Artemisia carvifolia (Buch.-Ham. ex Roxb. Hort. Beng.), Peganum harmala L. and Suaeda dendroides (C. A. Mey. Moq.) by using the cultural-dependent method. Then we classified these bacteria based on the difference between their sequences of 16S rRNA (16S ribosomal RNA) gene. Results showed that the isolated bacteria from R. soongorica belonged to the genera Brucella, Bacillus and Variovorax. The bacteria from A. carvifolia belonged to the genera Micromonospora and Brucella. The bacteria from P. harmala belonged to the genera Paramesorhizobium, Bacillus and Peribacillus. The bacteria from S. dendroides belonged to the genus Bacillus. Notably, the genus Bacillus was detected in the three above plants, indicating that Bacillus is a common taxon of endophytic bacteria in halophytes. And, our results found that about 37.50% of the tested strains showed strong protease-producing activity, 6.25% of the tested strains showed strong cellulase-producing activity and 12.50% of the tested strains showed moderate lipase-producing activity. Besides, all isolated strains were positive for IAA (3-Indoleacetic acid) production, 31.25% of isolated strains exhibited a moderate phosphate solubilization activity and 50.00% of isolated strains exhibited a weak siderophore production activity. Our findings suggest that halophytes are valuable resources for identifying microbes with the ability to increase host plant growth and health in salt-affected soils.

  • Development of a novel‐type transgenic cotton plant for control of cotton bollworm

    分类: 生物学 >> 植物学 >> 应用植物学 提交时间: 2016-05-04

    摘要: The transgenic Bt cotton plant has been widely planted throughout the world for the control of cotton budworm Helicoverpa armigera (Hubner). However, a shift towards insect tolerance of Btcotton is now apparent. In this study, the gene encoding neuropeptide F (NPF) was cloned from cotton budworm H.armigera, an important agricultural pest. The npf gene produces two splicing mRNA variantsnpf1 and npf2 (with a 120-bp segment inserted into the npf1 sequence). These are predicted to form the mature NPF1 and NPF2 peptides, and they were found to regulate feeding behaviour. Knock down of larval npf with dsNPF invitro resulted in decreases of food consumption and body weight, and dsNPF also caused a decrease of glycogen and an increase of trehalose. Moreover, we produced transgenic tobacco plants transiently expressing dsNPF and transgenic cotton plants with stably expressed dsNPF. Results showed that H.armigera larvae fed on these transgenic plants or leaves had lower food consumption, body size and body weight compared to controls. These results indicate that NPF is important in the control of feeding of H.armigera and valuable for production of potential transgenic cotton.

  • Ectopic expression of a cytochrome P450 monooxygenase gene PtCYP714A3 from Populus trichocarpa reduces shoot growth and improves tolerance to salt stress in transgenic rice

    分类: 生物学 >> 植物学 >> 植物生理学 提交时间: 2016-05-04

    摘要: In Arabidopsis thaliana and Oryza sativa, the cytochrome P450 (CYP) 714 protein family represents a unique group of CYP monooxygenase, which functions as a shoot-specific regulator in plant development through gibberellin deactivation. Here, we report the functional characterizations of PtCYP714A3, an OsCYP714D1/Eui homologue from Populus trichocarpa. PtCYP714A3 was ubiquitously expressed with the highest transcript level in cambiumphloem tissues, and was greatly induced by salt and osmotic stress in poplar. Subcellular localization analyses indicated that PtCYP714A3-YFP fusion protein was targeted to endoplasmic reticulum (ER). Expression of PtCYP714A3 in the rice eui mutant could rescue its excessive-shoot-growth phenotype. Ectopic expression of PtCYP714A3 in rice led to semi-dwarfed phenotype with promoted tillering and reduced seed size. Transgenic lines which showed significant expression of PtCYP714A3 also accumulated lower GA level than did the wild-type (WT) plants. The expression of some GA biosynthesis genes was significantly suppressed in these transgenic plants. Furthermore, transgenic rice plants exhibited enhanced tolerance to salt and maintained more Na+ in both shoot and root tissues under salinity stress. All these results not only suggest a crucial role of PtCYP714A3 in shoot responses to salt toxicity in rice, but also provide a molecular basis for genetic engineering of salt-tolerant crops.

  • AtTMEM18 plays important roles in pollen tube and vegetative growth in Arabidopsis

    分类: 生物学 >> 植物学 >> 植物生理学 提交时间: 2016-05-03

    摘要: In flowering plants, pollen tube growth is essential for delivery of male gametes into the female gametophyte or embryo sac for double fertilization. Although many genes have been identified as being involved in the process, the molecular mechanisms of pollen tube growth remains poorly understood. In this study, we identified that the Arabidopsis Transmembrane Protein 18 (AtTMEM18) gene played important roles in pollen tube growth. The AtTMEM18 shares a high similarity with the Transmembrane 18 proteins (TMEM18s) that are conserved in most eukaryotes and may play important roles in obesity in humans. Mutation in the AtTMEM18 by a Ds insertion caused abnormal callose deposition in the pollen grains and had a significant impact on pollen germination and pollen tube growth. AtTMEM18 is expressed in pollen grains, pollen tubes, root tips and other vegetative tissues. The pollen-rescued assays showed that the mutation in AtTMEM18 also caused defects in roots, stems, leaves and transmitting tracts. AtTMEM18-GFP was located around the nuclei. Genetic assays demonstrated that the localization of AtTMEM18 around the nuclei in the generative cells of pollen grains was essential for the male fertility. Furthermore, expression of the rice TMEM18-homologous protein (OsTMEM18) driven by LAT52 promoter could recover the fertility of the Arabidopsis attmem18 mutant. These results suggested that the TMEM18 is important for plant growth in Arabidopsis.

  • Endophytic bacteria associated with halophyte Seidlitzia rosmarinus Ehrenb. ex Boiss. from saline soil of Uzbekistan and their plant beneficial traits

    分类: 地球科学 >> 海洋科学 提交时间: 2020-11-25 合作期刊: 《干旱区科学》

    摘要: Endophytic bacteria of halophytic plants play essential roles in salt stress tolerance. Therefore, an understanding of the true nature of plant–microbe interactions under extreme conditions is essential. The current study aimed to identify cultivable endophytic bacteria associated with the roots and shoots of Seidlitzia rosmarinus Ehrenb. ex Boiss. grown in the salt-affected soil in Uzbekistan and to evaluate their plant beneficial traits related to plant growth stimulation and stress tolerance. Bacteria were isolated from the roots and the shoots of S. rosmarinus using culture-dependent techniques and identified by the 16S rRNA gene. RFLP (Restriction Fragment Length Polymorphism) analysis was conducted to eliminate similar isolates. Results showed that the isolates from the roots of S. rosmarinus belonged to the genera Rothia, Kocuria, Pseudomonas, Staphylococcus, Paenibacillus and Brevibacterium. The bacterial isolates from the shoots of S. rosmarinus belonged to the genera Staphylococcus, Rothia, Stenotrophomonas, Brevibacterium, Halomonas, Planococcus, Planomicrobium and Pseudomonas, which differed from those of the roots. Notably, Staphylococcus, Rothia and Brevibacterium were detected in both roots and shoots, indicating possible migration of some species from roots to shoots. The root-associated bacteria showed higher levels of IAA (indole-3-acetic acid) synthesis compared with those isolated from the shoots, as well as the higher production of ACC (1-aminocyclopropane-1-carboxylate) deaminase. Our findings suggest that halophytic plants are valuable sources for the selection of microbes with a potential to improve plant fitness under saline soils.

  • Characterization of Copper Complex Nanoparticles synthesized by Plant Polyphenols

    分类: 材料科学 >> 纳米科学和纳米技术 提交时间: 2017-05-07

    摘要: In this paper a kind of copper oxide material of copper–polyphenols complex nanoparticles (Cu–P NPs) were synthesized by Cinnamomum pedunculatum leaves extract, which have different morphology and appearance compared with usual copper oxides Cu2O and CuO. For better understanding about this material, the Cu–P NPs were characterized using scanning electron microscopy (SEM), X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). It was found that synthesized Cu–P NPs were amorphous with spherical particles ranged from 80 to 500 nm. XAS data analysis indicated that the synthesized Cu–P NPs has different molecular structure with Cu2O and CuO. It is assumed that the copper ions chelated with polyphenol molecule. The nanoparticles showed a clear anti Escherichia coli activity in this study, and may also be used in fields of semiconductor, ceramic, catalyst, and sensor. This synthesis approach provided a novel route to manufacture copper oxide nanomaterial.

  • Metabolic engineering for the production of plant isoquinoline alkaloids

    分类: 生物学 >> 植物学 >> 植物生物化学、植物生物物理学 提交时间: 2016-05-04

    摘要: Several plant isoquinoline alkaloids (PIAs) possess powerful pharmaceutical and biotechnological properties. Thus, PIA metabolism and its fascinating molecules, including morphine, colchicine and galanthamine, have attracted the attention of both the industry and researchers involved in plant science, biochemistry, chemical bioengineering and medicine. Currently, access and availability of high-value PIAs [commercialized (e.g. galanthamine) or not (e.g. narciclasine)] is limited by low concentration in nature, lack of cultivation or geographic access, seasonal production and risk of overharvesting wild plant species. Nevertheless, most commercial PIAs are still extracted from plant sources. Efforts to improve the production of PIA have largely been impaired by the lack of knowledge on PIA metabolism. With the development and integration of next-generation sequencing technologies, high-throughput proteomics and metabolomics analyses and bioinformatics, systems biology was used to unravel metabolic pathways allowing the use of metabolic engineering and synthetic biology approaches to increase production of valuable PIAs. Metabolic engineering provides opportunity to overcome issues related to restricted availability, diversification and productivity of plant alkaloids. Engineered plant, plant cells and microbial cell cultures can act as biofactories by offering their metabolic machinery for the purpose of optimizing the conditions and increasing the productivity of a specific alkaloid. In this article, is presented an update on the production of PIA in engineered plant, plant cell cultures and heterologous micro-organisms.

  • Exogenous addition of nitrate nitrogen regulates the uptake and translocation of lead (Pb) by Iris lacteal Pall. var. chinensis (Fisch.) Koidz.

    分类: 农、林、牧、渔 >> 农艺学 提交时间: 2023-02-16 合作期刊: 《干旱区科学》

    摘要: Since Pb is a non-biodegradable inorganic pollutant and a non-essential metal, its long-term presence in soil poses a great threat to the environment. Iris lactea Pall. var. chinensis (Fisch.) Koidz., a perennial dense bush herb with high resistance of Pb and wide adaptability, was used in pot experiments to study the effects of exogenous nitrate N (NO3-N) on the absorption and transportation of Pb and plant growth under different Pb concentrations. Then, the mechanism of NO3-N affecting Pb and nutrient uptake and transport was explored. The concentration of Pb in the experiment ranged from 0 to 1600 mg/kg, and the added concentration of NO3-N was 0.00.3 g/kg. The results showed that I. lactea was highly tolerant to Pb, and the shoot fraction was more sensitive to varied Pb concentrations in the soil than the root fraction. This protective function became more pronounced under the condition of raised Pb concentration in the soil. When the concentration of Pb in the soil reached 800 mg/kg, the highest Pb content of I. lactea was found under the condition of 0.1 g/kg of NO3-N addition. When Pb concentration in the soil increased to 1600 mg/kg, the increase in NO3-N addition promoted Pb uptake by the root. To ensure the well growth of I. lactea and the effect of remediation of Pb-contaminated soil, the recommended concentration of NO3-N in the soil is 0.1 g/kg. This result provides a theoretical basis for exogenous N regulation of phytoremediation of Pb-contaminated soil.

  • Responses of plant community to the linkages in plant–soil C:N:P stoichiometry during secondary succession of abandoned farmlands, China

    分类: 地球科学 >> 地球科学史 提交时间: 2020-06-22 合作期刊: 《干旱区科学》

    摘要: Succession is one of the central themes of ecology; however, the relationship between aboveground plant communities and underground soils during secondary succession remains unclear. In this study, we investigated the composition of plant community, plant–soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0, 10, 20, 30, 40 and 50 a in China, 2016. Results showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 a. Soil organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a, but both were significantly higher than those of control farmland (31.21%–139.10% and 24.24%–121.21%, respectively). Moreover, C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands, explaining 35.70% of the total variation. Particularly, soil C:N ratio was significantly and positively related with the Shannon–Wiener index. This study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.

  • Fusarium oxysporum mediates systems metabolic reprogramming of chickpea roots as revealed by a combination of proteomics and metabolomics

    分类: 生物学 >> 植物学 >> 植物生物化学、植物生物物理学 提交时间: 2016-05-04

    摘要: Molecular changes elicited by plants in response to fungal attack and how this affects plantpathogen interaction, including susceptibility or resistance, remain elusive. We studied the dynamics in root metabolism during compatible and incompatible interactions between chickpea and Fusarium oxysporum f. sp. ciceri (Foc), using quantitative label-free proteomics and NMR-based metabolomics. Results demonstrated differential expression of proteins and metabolites upon Foc inoculations in the resistant plants compared with the susceptible ones. Additionally, expression analysis of candidate genes supported the proteomic and metabolic variations in the chickpea roots upon Foc inoculation. In particular, we found that the resistant plants revealed significant increase in the carbon and nitrogen metabolism; generation of reactive oxygen species (ROS), lignification and phytoalexins. The levels of some of the pathogenesis-related proteins were significantly higher upon Foc inoculation in the resistant plant. Interestingly, results also exhibited the crucial role of altered Yang cycle, which contributed in different methylation reactions and unfolded protein response in the chickpea roots against Foc. Overall, the observed modulations in the metabolic flux as outcome of several orchestrated molecular events are determinant of plant's role in chickpeaFoc interactions.