DataSheet_1_Autotoxicity in Panax notoginseng of root exudatesand their allelochemicals.pdf

The growth of Panax notoginseng (Burk.) F. H. Chen is frequently hindered due to replanting failure. In the present study, the objective is to determine whether root exudates from P. notoginseng have autotoxicity and identification of allelochemicals from root exudates or rhizosphere soil. We investigated autotoxicity in P. notoginseng using seedling emergence bioassays and hydroponic culture. The allelochemicals in the soils and root exudates were identified with GC-MS, and the autotoxicity of the identified key allelochemicals was investigated by bioassay. The results showed that the root exudates, and extracts from consecutively cultivated soils also showed significant autotoxicity against seedling emergence and growth. In the non-renewed culture solution without activated charcoal (AC), the fresh and dry mass of P. notoginseng tubers of roots was reduced by about half compared to the addition with AC. A total of 44 different components from all samples were defined by GC-MS analyses. Furthermore, the results of multiple statistical analysis showed a t the difference among cultivated soil, uncultivated soil and root exudates. Bioassay of the identified allelochemicals revealed that benzoic acid, phthalic acid, palmitic acid, and stearic acid significantly affected the root growth of P. notoginseng. These substances at 100 μM more significantly decreased the number of lateral roots. Our results demonstrated that autotoxicity results in replant failure of P. notoginseng.</p

Image_1_Bacteria from nodules of Abrus mollis Hance: genetic diversity and screening of highly efficient growth-promoting strains.pdf

IntroductionAbrus mollis Hance. (AM) is an important species used in southern Chinese medicine. It is mainly found in Guangdong and Guangxi provinces in China, and it is effective in the treatment of hepatitis. Endophytic bacteria are known to affect the growth and quality of medicinal plants. However, there are limited reports describing endophytic bacteria related to AM.MethodsIn the present study, Illumina-based 16S rRNA gene sequencing was used to investigate the endophytic bacterial communities of root nodules of AM at five sampling sites in Guangxi. In addition, 179 strains of endophytic bacteria were isolated and categorized into 13 haplotypes based on recA sequence analysis.ResultsThe phylogeny of the 16S rRNA gene sequences revealed a predominance of nonrhizobial endophytes. Microbial diversity analysis showed that Proteobacteria was the dominant phylum in all samples, while Bradyrhizobium was the dominant genus in different samples. An efficient strain, Rhizobium tropici FM-19, was screened and obtained through greenhouse experiments. The AM plants inoculated with this strain showed the best growth performance and high nitrogen fixation and nodulation capacity. Notably, total phenols and total flavonoids, important active components in AM, increased by 30.9 and 42.7%, respectively, after inoculation with Rhizobium tropici FM-19.DiscussionThis study provides insights into the complex microbial diversity of AM nodules and provides strain information for the efficient cultivation of AM.</p

Table_1_Genome-Wide Identification of R2R3-MYB Transcription Factors: Discovery of a “Dual-Function” Regulator of Gypenoside and Flavonol Biosynthesis in Gynostemma pentaphyllum.XLSX

The R2R3-MYB gene family participates in several plant physiological processes, especially the regulation of the biosynthesis of secondary metabolites. However, little is known about the functions of R2R3-MYB genes in Gynostemma pentaphyllum (G. pentaphyllum), a traditional Chinese medicinal herb that is an excellent source of gypenosides (a class of triterpenoid saponins) and flavonoids. In this study, a systematic genome-wide analysis of the R2R3-MYB gene family was performed using the recently sequenced G. pentaphyllum genome. In total, 87 R2R3-GpMYB genes were identified and subsequently divided into 32 subgroups based on phylogenetic analysis. The analysis was based on conserved exon–intron structures and motif compositions within the same subgroup. Collinearity analysis demonstrated that segmental duplication events were majorly responsible for the expansion of the R2R3-GpMYB gene family, and Ka/Ks analysis indicated that the majority of the duplicated R2R3-GpMYB genes underwent purifying selection. A combination of transcriptome analysis and quantitative reverse transcriptase-PCR (qRT-PCR) confirmed that Gynostemma pentaphyllum myeloblastosis 81 (GpMYB81) along with genes encoding gypenoside and flavonol biosynthetic enzymes exhibited similar expression patterns in different tissues and responses to methyl jasmonate (MeJA). Moreover, GpMYB81 could bind to the promoters of Gynostemma pentaphyllum farnesyl pyrophosphate synthase 1 (GpFPS1) and Gynostemma pentaphyllum chalcone synthase (GpCHS), the key structural genes of gypenoside and flavonol biosynthesis, respectively, and activate their expression. Altogether, this study highlights a novel transcriptional regulatory mechanism that suggests that GpMYB81 acts as a “dual-function” regulator of gypenoside and flavonol biosynthesis in G. pentaphyllum.</p

Supplementary document for On-line high-accuracy particulate matter monitoring technology by using multi-channel scattering signals - 5464515.pdf

Supplement

Additional file 1 of Genome-wide characterization of the bHLH gene family in Gynostemma pentaphyllum reveals its potential role in the regulation of gypenoside biosynthesis

Additional file 1: Table S1. Characteristics of the 111 bHLH genes in Gynostemma pentaphyllum of this study

Selection and Validation of Suitable Reference Genes for Gene Expression Studies in <i>Callerya speciosa</i> (Champ. ex Benth.) Schot under Different Experimental Conditions

The accuracy of reverse transcription quantitative real-time PCR (RT-qPCR) strongly depends on the stability of reference gene. It is essential to select a suitable reference gene in order to obtain reliable RT-qPCR results when gene expression profiles were evaluated. Callerya speciosa, a traditional Chinese medicine, has a long cultivation history in south China. However, suitable reference genes in C. speciosa have not yet been investigated for accurate gene expression quantification under different experimental conditions. In this study, eight candidate reference genes, including GAPDH (glyceraldehyde-3-phosphate dehydrogenase), 60S (60S ribosomal protein L34), ACTIN (actin), TUA2 (tubulin alpha chain), TUB1 (tubulin beta-1 chain), TIF5 (eukaryotic translation initiation factor 5A), UBQ (polyubiquitin), and EF2 (elongation factor 2), were selected from the transcriptome databases, and their expression stability under six different experimental conditions (developmental stages, tissues, MeJA treatment, GA3 treatment, CPPU treatment, and PP333 treatment) was evaluated using ΔCT, geNorm, NormFinder, BestKeeper, and RefFinder programs. The results showed that GAPDH was the optimal reference gene for all different experimental conditions, whereas ACTIN showed the best stability under most of the hormone treatments. TUA2 and EF2 were the two least suitable ones as reference genes in C. speciosa. The expression pattern of CsMYB36, a gene associated with the regulation of isoflavonoid biosynthesis in C. speciosa, verified the accuracy of our experimental results. These results provided a theoretical basis for subsequent research on the regulation of functional gene expression in C. speciosa and other Callerya species in the future

Selection and Validation of Suitable Reference Genes for Gene Expression Studies in <i>Callerya speciosa</i> (Champ. ex Benth.) Schot under Different Experimental Conditions

The accuracy of reverse transcription quantitative real-time PCR (RT-qPCR) strongly depends on the stability of reference gene. It is essential to select a suitable reference gene in order to obtain reliable RT-qPCR results when gene expression profiles were evaluated. Callerya speciosa, a traditional Chinese medicine, has a long cultivation history in south China. However, suitable reference genes in C. speciosa have not yet been investigated for accurate gene expression quantification under different experimental conditions. In this study, eight candidate reference genes, including GAPDH (glyceraldehyde-3-phosphate dehydrogenase), 60S (60S ribosomal protein L34), ACTIN (actin), TUA2 (tubulin alpha chain), TUB1 (tubulin beta-1 chain), TIF5 (eukaryotic translation initiation factor 5A), UBQ (polyubiquitin), and EF2 (elongation factor 2), were selected from the transcriptome databases, and their expression stability under six different experimental conditions (developmental stages, tissues, MeJA treatment, GA3 treatment, CPPU treatment, and PP333 treatment) was evaluated using ΔCT, geNorm, NormFinder, BestKeeper, and RefFinder programs. The results showed that GAPDH was the optimal reference gene for all different experimental conditions, whereas ACTIN showed the best stability under most of the hormone treatments. TUA2 and EF2 were the two least suitable ones as reference genes in C. speciosa. The expression pattern of CsMYB36, a gene associated with the regulation of isoflavonoid biosynthesis in C. speciosa, verified the accuracy of our experimental results. These results provided a theoretical basis for subsequent research on the regulation of functional gene expression in C. speciosa and other Callerya species in the future

Selection and Validation of Suitable Reference Genes for Gene Expression Studies in <i>Callerya speciosa</i> (Champ. ex Benth.) Schot under Different Experimental Conditions

The accuracy of reverse transcription quantitative real-time PCR (RT-qPCR) strongly depends on the stability of reference gene. It is essential to select a suitable reference gene in order to obtain reliable RT-qPCR results when gene expression profiles were evaluated. Callerya speciosa, a traditional Chinese medicine, has a long cultivation history in south China. However, suitable reference genes in C. speciosa have not yet been investigated for accurate gene expression quantification under different experimental conditions. In this study, eight candidate reference genes, including GAPDH (glyceraldehyde-3-phosphate dehydrogenase), 60S (60S ribosomal protein L34), ACTIN (actin), TUA2 (tubulin alpha chain), TUB1 (tubulin beta-1 chain), TIF5 (eukaryotic translation initiation factor 5A), UBQ (polyubiquitin), and EF2 (elongation factor 2), were selected from the transcriptome databases, and their expression stability under six different experimental conditions (developmental stages, tissues, MeJA treatment, GA3 treatment, CPPU treatment, and PP333 treatment) was evaluated using ΔCT, geNorm, NormFinder, BestKeeper, and RefFinder programs. The results showed that GAPDH was the optimal reference gene for all different experimental conditions, whereas ACTIN showed the best stability under most of the hormone treatments. TUA2 and EF2 were the two least suitable ones as reference genes in C. speciosa. The expression pattern of CsMYB36, a gene associated with the regulation of isoflavonoid biosynthesis in C. speciosa, verified the accuracy of our experimental results. These results provided a theoretical basis for subsequent research on the regulation of functional gene expression in C. speciosa and other Callerya species in the future