Properties and Fungal Communities of Different Soils for Growth of the Medicinal Asian Water Plantain, Alisma orientale, in Fujian, China.

The Asian water plantain, Alisma orientale (Sam.) Juzep, is a traditional Chinese medicinal plant. The dried tubers of the Alisma orientale, commonly referred to as Alismatis rhizome (AR), have long been used in traditional Chinese medicine to treat a variety of diseases. Soil properties and the soil microbial composition are known to affect the quality and bioactivity of plants. Here, we sought to identify variations in soil fungal communities and soil properties to determine which would be optimal for cultivation of A. orietale. Soil properties, heavy metal content, and pesticide residues were determined from soils derived from four different agricultural regions around Shaowu City, Fujian, China, that had previously been cultivated with various crops, namely, Shui Dao Tu (SDT, rice), Guo Shu Tu (GST, pecan), Cha Shu Tu (CST, tea trees), and Sang Shen Tu (SST, mulberry). As fungi can either positively or negatively impact plant growth, the fungal communities in the different soils were characterized using long-read PacBio sequencing. Finally, we examined the quality of A. orientale grown in the different soils. Our results show that fungal community diversity of the GST soil was the highest with saprotrophs the main functional modes in these and SDT soils. Our data show that GST and SDT soils were most suitable for A. orientale growth, with the quality of the AR tubers harvested from GST soil being the highest. These data provide a systematic approach at soil properties of agricultural lands in need of replacement and/or rotating crops. Based on our findings, GST was identified as the optimal soil for planting A. orientale, providing a new resource for local farmers.

[Evolution mechanism of ecosystem service value at the township-scale in Anxi County of Fujian Province, China]. / 福建安溪县乡镇土地生态系统服务价值的演变机制.

To clarify the interaction between land-use change and ecosystem service, the traditional ecosystem service valuation model was modified using the adjustment coefficients of biomass factor and socio-economic factor to evaluate ecosystem service value (ESV) of 24 towns in Anxi County from 1999 to 2019, aiming to understand the ecological response to land-use change. The results showed that ESV of 24 towns in Anxi County decreased gradually during the study period, with a decrease of 0.004 to 0.295 million yuan. Forestland and cultivated land made the largest contribution to ESV, followed by grassland and water bodies, whereas the contribution of other land types were negative. ESV could be increased by converting other land types into forestland, but be decreased by converting other land types into orchard land area (mainly tea plantation). The chemical fertilizer-monoculture management pattern of ratooning tea plantation reduced ESV, while the ecological cultivation of tea plantation could effectively improve soil microbial diversity and soil fertility, and finally enhance ESV.

High-Quality Genome of the Medicinal Plant Strobilanthes cusia Provides Insights Into the Biosynthesis of Indole Alkaloids.

Strobilanthes cusia (Nees) Kuntze is an important plant used to process the traditional Chinese herbal medicines "Qingdai" and "Nanbanlangen". The key active ingredients are indole alkaloids (IAs) that exert antibacterial, antiviral, and antitumor pharmacological activities and serve as natural dyes. We assembled the S. cusia genome at the chromosome level through combined PacBio circular consensus sequencing (CCS) and Hi-C sequencing data. Hi-C data revealed a draft genome size of 913.74 Mb, with 904.18 Mb contigs anchored into 16 pseudo-chromosomes. Contig N50 and scaffold N50 were 35.59 and 68.44 Mb, respectively. Of the 32,974 predicted protein-coding genes, 96.52% were functionally annotated in public databases. We predicted 675.66 Mb repetitive sequences, 47.08% of sequences were long terminal repeat (LTR) retrotransposons. Moreover, 983 Strobilanthes-specific genes (SSGs) were identified for the first time, accounting for ~2.98% of all protein-coding genes. Further, 245 putative centromeric and 29 putative telomeric fragments were identified. The transcriptome analysis identified 2,975 differentially expressed genes (DEGs) enriched in phenylpropanoid, flavonoid, and triterpenoid biosynthesis. This systematic characterization of key enzyme-coding genes associated with the IA pathway and basic helix-loop-helix (bHLH) transcription factor family formed a network from the shikimate pathway to the indole alkaloid synthesis pathway in S. cusia. The high-quality S. cusia genome presented herein is an essential resource for the traditional Chinese medicine genomics studies and understanding the genetic underpinning of IA biosynthesis.

Molecular cloning and metabolomic characterization of the 5-enolpyruvylshikimate-3-phosphate synthase gene from Baphicacanthus cusia.

BACKGROUND: Indigo alkaloids, such as indigo, indirubin and its derivatives, have been identified as effective antiviral compounds in Baphicacanthus cusia. Evidence suggests that the biosynthesis of indigo alkaloids in plants occurs via the shikimate pathway. The enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) is involved in plant metabolism; however, its underlying putative mechanism of regulating the production of indigo alkaloids is currently unknown. RESULTS: One gene encoding EPSPS was isolated from B. cusia. Quantitative real-time PCR analysis revealed that BcEPSPS was expressed at the highest level in the stem and upregulated by methyl jasmonate (MeJA), salicylic acid (SA) and abscisic acid (ABA) treatment. The results of subcellular localization indicated that BcEPSPS is mainly expressed in both the plastids and cytosol, which has not been previously reported. An enzyme assay revealed that the heterogeneously expressed BcEPSPS protein catalysed the generation of 5-enolpyruvyl shikimate-3-phosphate. The overexpression of BcEPSPS in Isatis indigotica hairy roots resulted in the high accumulation of indigo alkaloids, such as indigo, secologanin, indole and isorhamnetin. CONCLUSIONS: The function of BcEPSPS in catalysing the production of EPSP and regulating indigo alkaloid biosynthesis was revealed, which provided a distinct view of plant metabolic engineering. Our findings have practical implications for understanding the effect of BcEPSPS on active compound biosynthesis in B. cusia.

Comparative transcriptome analyses revealed differential strategies of roots and leaves from methyl jasmonate treatment Baphicacanthus cusia (Nees) Bremek and differentially expressed genes involved in tryptophan biosynthesis.

Baphicacanthus cusia (Nees) Bremek (B. cusia) is an effective herb for the treatment of acute promyelocytic leukemia and psoriasis in traditional Chinese medicine. Methyl jasmonate (MeJA) is a well-known signaling phytohormone that triggers gene expression in secondary metabolism. Currently, MeJA-mediated biosynthesis of indigo and indirubin in B. cusia is not well understood. In this study, we analyzed the content of indigo and indirubin in leaf and root tissues of B. cusia with high-performance liquid chromatography and measured photosynthetic characteristics of leaves treated by MeJA using FluorCam6 Fluorometer and chlorophyll fluorescence using the portable photosynthesis system CIRAS-2. We performed de novo RNA-seq of B. cusia leaf and root transcriptional profiles to investigate differentially expressed genes (DEGs) in response to exogenous MeJA application. The amount of indigo in MeJA-treated leaves were higher than that in controled leaves (p = 0.004), and the amounts of indigo in treated roots was higher than that in controlled roots (p = 0.048); Chlorophyll fluorescence of leaves treated with MeJA were significantly decreased. Leaves treated with MeJA showed lower photosynthetic rate compared to the control in the absence of MeJA. Functional annotation of DEGs showed the DEGs related to growth and development processes were down-regulated in the treated leaves, while most of the unigenes involved in the defense response were up-regulated in treated roots. This coincided with the effects of MeJA on photosynthetic characteristics and chlorophyll fluorescence. The qRT-PCR results showed that MeJA appears to down-regulate the gene expression of tryptophan synthase ß-subunits (trpA-ß) in leaves but increased the gene expression of anthranilate synthase (trp 3) in roots responsible for increased indigo content. The results showed that MeJA suppressed leaf photosynthesis for B. cusia and this growth-defense trade-off may contribute to the improved adaptability of B. cusia in changing environments.

De novo characterization of the Baphicacanthus cusia(Nees) Bremek transcriptome and analysis of candidate genes involved in indican biosynthesis and metabolism.

Baphicacanthus cusia (Nees) Bremek is an herb widely used for the clinical treatment of colds, fever, and influenza in Traditional Chinese Medicine. The roots, stems and leaves can be used as natural medicine, in which indigo and indirubin are two main active ingredients. In this study, quantification of indigo, indirubin, indican and adenosine among various tissues of B. cusia was conducted using HPLC-DAD. Leaves have significantly higher contents than stems and roots (380.66, 315.15, 20,978.26, 4323.15 µg/g in leaves, 306.36, 71.71, 3,056.78, 139.45 µg/g in stems, and 9.31, 7.82, 170.45, 197.48 µg/g in roots, respectively). De novo transcriptome sequencing of B. cusia was performed for the first time. The sequencing yielded 137,216,248, 122,837,394 and 140,240,688 clean reads from leaves, stems and roots respectively, which were assembled into 51,381 unique sequences. A total of 33,317 unigenes could be annotated using the databases of Nr, Swiss-Prot, KEGG and KOG. These analyses provided a detailed view of the enzymes involved in indican backbone biosynthesis, such as cytochrome P450, UDP-glycosyltransferase, glucosidase and tryptophan synthase. Analysis results showed that tryptophan synthase was the candidate gene involved in the tissue-specific biosynthesis of indican. We also detected sixteen types of simple sequence repeats in RNA-Seq data for use in future molecular mark assisted breeding studies. The results will be helpful in further analysis of B. cusia functional genomics, especially in increasing biosynthesis of indican through biotechnological approaches and metabolic regulation.

[Bioinformation analysis of chorismate synthase in Baphicacantus cusia and other 78 species of plants].

Chorismate synthase(CS, EC:4.2.3.5) catalyses 5-enolpyruvy-shikimate-3-phosphate to form chorismate, which is the essential enzyme for chorismate biosynthesis in organisms. The amino acid sequences of CS from 79 species of higher plants were reported in GenBank at present. 125 amino acid sequences of CS from Baphicacanthus cusia and other 78 species of plants were predicted and analyzed by using various bioinformatics software, including the composition of amino acid sequences, signal peptide, leader peptide, hydrophobic/hydrophilic, transmembrane structure, coiled-coil domain, protein secondary structure, tertiary structure and functional domains. The phylogenetic tree of CS protein family was constructed and divided into eight groups by phylogenetic analysis. The homology comparison indicated that B. cusia shared a high homology with several plants such as Sesamum indicum, Nicotiana tabacum, Solanum tuberosum and so on. The open reading frame(ORF) of all samples is about 1 300 bp, the molecular weight is about 50 kDa, the isoelectric point(pI) is 5.0-8.0 which illustrated that CS protein is slightly basic. The ORF of CS we cloned in B. cusia is 1 326 bp, the amino acid residues are 442, the molecular weight is 47 kDa and pI is 8.11. The CS in B.cusia showed obvious hydrophobicity area and hydrophilicity area, no signal peptide, and may exists transmembrane structure areas. The main secondary structures of CS protein are random coil and Alpha helix, also contain three main structural domains which are an active structural domain, a PLN02754 conserved domain and a FMN binding site. The acquired information in this study would provide certain scientific basis for further study on structure-activity relationship and structure modification of CS in plants in the future.

[Effects of exogenous salicylic acid on protein expression level in Baphicacanthus cusia (Nees) Bremek leaves].

By using two-dimensional eletrophoresis method, this paper studied the protein expression level in Baphicacanthus cusia (Nees) Bremek leaves after sprayed with exogenous salicylic acid (SA). A total of significantly different 20 protein spots were obtained, among which, eight protein spots were indentified, being of ATP synthase, alpha tubulin, cell division protein, glyceraldehydephosphate dehydrogenase, and ACC oxidase, respectively. The expression abundance of all identified proteins was up-regulated, except for ACC oxidase which was down-regulated. Therefore, exogenous SA could affect the protein expression level in B. cusia leaves, and improve the plant resistance to environment stress and self-restoration capability.

[Proteomics of rice leaf and grain at late growth stage under different nitrogen fertilization levels].

Taking super-rice Liangyoupeijiu as test material, and by the method of two-dimensional gel electrophoresis (2-DE), this paper studied the changes in the leaf and grain proteomics of the variety at its late growth stage under different levels of nitrogen fertilization (1/2 times of normal nitrogen level, 20 mg x L(-1); normal nitrogen level, 40 mg x L(-1); 2 times of normal nitrogen level, 80 mg x L(-1)), with the biological functions of 16 leaf proteins, 9 inferior grain proteins, and 4 superior grain proteins identified and analyzed. Nitrogen fertilization could affect and regulate the plant photosynthesis via affecting the activation of photosynthesis-related enzymes and of CO2, the light system unit, and the constitution of electron transfer chain at the late growth stage of the variety. It could also promote the expression of the enzymes related to the energy synthesis and growth in inferior grains. High nitrogen fertilization level was not beneficial to the synthesis of starch in superior grain, but sufficient nitrogen supply was still important for the substance accumulation and metabolism. Therefore, rational nitrogen fertilization could increase the photosynthesis rate of flag leaves, enhance the source function, delay the functional early ageing, and promote the grain-filling at late growth stage.

[Studies on identification of Gryllotalpa by near-infrared diffuse reflectance spectrometry].

OBJECTIVE: To identify and analyse the different species, same species in different regions and confusion species. METHOD: Near-infrared diffuse reflectance spectrometry was used. RESULT: Clustering analysis showed that clustering relations were far among different Gryllotalpa species and close among the same species from different regions, and there were close relations among the same species from near regions and between Teleogryllus emmus and G. orientalis. CONCLUSION: Near-infrared diffuse reflectance spectrometry method can be used in classification and identification of Gryllotalpa.

[Relationship between wheat root activity and leaf senescence].

A field trial on the wheat root activity, chlorophyll content and photosynthetic rate showed that the decline of root activity was earlier and faster than that of flag leaf chlorophyll content and photosynthetic rate, and there was a positive correlation between root activity and leaf photosynthetic rate (r = 0.8006). Topdressing nitrogen fertilizer at elongation stage could obviously improve root activity and photosynthetic rate, decrease leaf ABA content, increase ZRs content and SOD activity, and delay the peak value of MDA for 8-10 days, which suggested that the variation of root activity was closely related to the senescence of flag leaf. Improving root nutrition and root activity at earlier growth stages could delay the senescence of wheatleaf.

[Effect of hormones on regulating and controlling photosynthesis rate of wheat nag leaf at their different development phases].

By the method of ELASA, this paper measured the ABA/ZRs ratio in wheat flag leaf at the relative steady phase (RSP), end steady phase (ESP) and sharply descending phase (SFP) of chlorophylls. The ABA, ZRs and their mixture were led to the transpiration current of plant to measure the changes of photosynthesis rate at these three phases. The results showed that the ABA/ZRs ratio in flag leaf was 4.20, 41.83 and 14.40 at RSP, ESP and SFP, respectively. The time that the photosynthesis rate reduced by ABA to zero was 49.5, 39.1 and 38.0 min, and that reduced by ZRs to half was 65, 49 and 31 min, respectively. The two preceding phases could be regulated, and the changes were reversible.