Pseudostellaria heterophylla improves intestinal microecology through modulating gut microbiota and metabolites in mice.

Background: Pseudostellaria heterophylla is a Chinese medicine and healthy edible that is widely used to for its immunomodulatory, antioxidant, antidiabetic and antitussive properties. However, the potential function of P. heterophylla in intestinal microecology remains unclear.

Effects of C isotope-labeled allelochemicals on the growth of the invasive plant Alternanthera philoxeroides.

The secondary metabolites of indigenous plants have significant allelopathic inhibitory effects on the growth and development of invasive alien plants. Methyl palmitate (MP) and methyl linolenate (ML) were used as exogenous allelopathic substances. The research investigated the differences of inhibitory effects of MP and ML on the growth of seedlings of Alternanthera philoxeroides, and calculated their morphological characteristics, biomass, physiological indicators and the response index (RI).

Bio-fertilizer Amendment Alleviates the Replanting Disease under Consecutive Monoculture Regimes by Reshaping Leaf and Root Microbiome.

Replanting disease is a growing problem in intensive agricultural systems. Application of bio-fertilizer containing beneficial microbes contributes to disease suppression and is a promising strategy to control replanting disease. However, the effect of both replanting disease and bio-fertilizer amendment on the assembly of crop microbiota in leaves and roots and their relationships to crop yield and quality remains elusive.

Effects of different technical substitutions on reducing replant disease of and the underlying mechanism.

is a traditional Chinese medicinical herb, with tuberous roots being used as a medicine. Serious continuous monoculture problems were suffered from process of artificial and intensive cultivation. To explore the effective technical methods to overcome the monoculture problems, the effects of different technical substitution patterns on soil environment remediation, photosynthetic physiology and yield performance of were assessed under continuous cropping system with four technical substitution treatments in the phase between two crops after the newly harvested (first crop): fallow (RP-F-RP), fallow treated with microbial fertilizer (RP-F-BF), water flooding (RP-WF), and water flooding treated with specific microbial fertilizer (RP-WF-BF).

Revealing Microbiome Structure and Assembly Process in Three Rhizocompartments of Under Continuous Monoculture Regimes.

The complex composition and interaction of root-associated microbes are critical to plant health and performance. In this study, we presented a detailed characterization of three rhizocompartment (rhizosphere, rhizoplane, and root) microbiomes of under different years of consecutive monoculture by deep sequencing in order to determine keystone microorganisms co-occurrence network analysis. The network analysis showed that multiple consecutive monoculture (MCM, represented 5Y and 10Y) soils generated some distinct beneficial bacterial taxa such as , , , , and .

Antagonistic Activity of spp. Against in Rhizosphere of Triggers the Expression of Host Defense Genes and Improves Its Growth Under Long-Term Monoculture System.

Under consecutive monoculture, the abundance of pathogenic fungi, such as in the rhizosphere of , negatively affects the yield and quality of the plant. Therefore, it is pertinent to explore the role of antagonistic fungi for the management of fungal pathogens such as Our PCR-denatured gradient gel electrophoresis (DGGE) results revealed that the diversity of spp. was significantly declined due to extended monoculture.

First Report of Mucor spp. Causing Root Rot of Radix pseudstellariae in Guizhou Province of China.

Radix pseudostellariae L. is one of the most common and highly-prized Chinese medicinal plants with various pharmacological effects, and mainly produced in acid soils in the Guizhou and Fujian provinces of southwestern and southeastern China, respectively (Wu et al. 2020).

Linking Short-Chain N-Acyl Homoserine Lactone-Mediated Quorum Sensing and Replant Disease: A Case Study of .

, a perennial medicinal plant, suffers from severe replant disease under consecutive monoculture. The rhizosphere microbiome is vital for soil suppressiveness to diseases and for plant health. Moreover, N-acyl homoserine lactone (AHL)-mediated quorum sensing (QS) regulates diverse behavior in rhizosphere-inhabiting and plant pathogenic bacteria.

Underlying Mechanism of Wild in Tolerance to Disease Under the Natural Forest Cover.

Replanting disease caused by negative plant-soil feedback in continuous monoculture of is a critical factor restricting the development of this common and popular Chinese medicine, although wild plants were shown to grow well without occurrence of disease in the same site for multiple years. Therefore, we aimed to identify the changes in microbial community composition in the rhizosphere soil of wild thus providing a potential method for controlling soil-borne diseases. We analyzed differences in soil physicochemical properties, changes in soil microbial community structure, and root exudates of wild under different biotopes.

Stereospecific Electrophilic Fluorocyclization of α,β-Unsaturated Amides with Selectfluor.

An efficient fluorocyclization of ,-unsaturated amides through a formal halocyclization process is developed. The reaction proceeds under transition-metal-free conditions and leads to the formation of fluorinated oxazolidine-2,4-diones with excellent regio- and diastereoselectivity. The evaluation of the reaction mechanism based on preliminary experiments and density functional theory calculations suggests that a synergetic -oxo-fluorination occurs and is followed by an -oxo substitution reaction.

Biochar mediates microbial communities and their metabolic characteristics under continuous monoculture.

Biochar amendment has been extensively used to improve plant performance and suppress disease in monoculture systems; however, few studies have focused on the underlying control mechanisms of replanting disease. In this study, we assessed the effects of biochar application on Radix pseudostellariae plant growth, rhizosphere soil microbial communities, and the physiological properties of microorganisms in a consecutive monoculture system. We found that biochar addition had little impact on the physiological parameters of tissue cultures of R.

Nitrogen Fertilizer Amendment Alter the Bacterial Community Structure in the Rhizosphere of Rice ( L.) and Improve Crop Yield.

Availability of nitrogen (N) in soil changes the composition and activities of microbial community, which is critical for the processing of soil organic matter and health of crop plants. Inappropriate application of N fertilizer can alter the rhizosphere microbial community and disturb the soil N homeostasis. The goal of this study was to assess the effect of different ratio of N fertilizer at various early to late growth stages of rice, while keeping the total N supply constant on rice growth performance, microbial community structure, and soil protein expression in rice rhizosphere.

Modification of Rhizosphere Bacterial Community Structure and Functional Potentials to Control Replant Disease.

Replant disease caused by negative plant-soil feedback commonly occurs in a monoculture regime. Here, barcoded pyrosequencing of 16S ribosomal DNA amplicons combined with phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis was applied to study the shifts in soil bacterial community structure and functional potentials in the rhizosphere of under consecutive monoculture and different soil amendments (i.e.

The effects of chemical and organic fertilizer usage on rhizosphere soil in tea orchards.

Sustainable agriculture is an important global issue. The use of organic fertilizers can enhance crop yield and soil properties while restraining pests and diseases. The objective of this study was to assess the effects of long-term use of chemical and organic fertilizers on tea and rhizosphere soil properties in tea orchards.

Comparative Metagenomic Analysis of Rhizosphere Microbial Community Composition and Functional Potentials under Consecutive Monoculture.

Consecutive monoculture of , highly valued in traditional Chinese medicine, leads to a severe decline in both quality and yield. Rhizosphere microbiome was reported to be closely associated with the soil health and plant performance. In this study, comparative metagenomics was applied to investigate the shifts in rhizosphere microbial structures and functional potentials under consecutive monoculture.

Rhizosphere Fungal Community Dynamics Associated with Rehmannia glutinosa Replant Disease in a Consecutive Monoculture Regime.

Consecutive monoculture of Rehmannia glutinosa in the same field leads to a severe decline in both quality and yield of tuberous roots, the most useful part in traditional Chinese medicine. Fungi are an important and diverse group of microorganisms in the soil ecosystem and play crucial roles in soil health. In this study, high-throughput pyrosequencing of internal transcribed spacer 2 ribosomal DNA amplicons was applied to gain insight into how consecutive monoculture practice influence and stimulate R.

Barcoded Pyrosequencing Reveals a Shift in the Bacterial Community in the Rhizosphere and Rhizoplane of Rehmannia glutinosa under Consecutive Monoculture.

The production and quality of can be dramatically reduced by replant disease under consecutive monoculture. The root-associated microbiome, also known as the second genome of the plant, was investigated to understand its impact on plant health. Culture-dependent and culture-independent pyrosequencing analysis was applied to assess the shifts in soil bacterial communities in the rhizosphere and rhizoplane under consecutive monoculture.

Assessment of the Diversity of spp. and spp. in Rhizosphere under Monoculture by Combining DGGE and Quantitative PCR.

is a perennial tonic medicinal plant, with high medicinal value. However, consecutive monoculture of this plant in the same field results in serious decrease in both yield and quality. In this study, a 3-year field experiment was performed to identify the inhibitory effect of growth caused by prolonged monoculture of .

Transcriptome analysis of Pseudostellaria heterophylla in response to the infection of pathogenic Fusarium oxysporum.

Background: Pseudostellaria heterophylla (P. heterophylla), a herbaceous perennial, belongs to Caryophyllaceae family and is one of the Chinese herbal medicine with high pharmacodynamic value. It can be used to treat the spleen deficiency, anorexia, weakness after illness and spontaneous perspiration symptoms.

The role of organic acids on microbial deterioration in the Radix pseudostellariae rhizosphere under continuous monoculture regimes.

A three-year field monoculture trial of Radix pseudostellariae and complementary laboratory studies were conducted to further elucidate the underlying mechanism responsible for significant decreases in the biomass yield and quality of R. pseudostellariae under continuous monoculture regimes. HPLC analysis indicated that continuous monoculture soil was rich in organic acids, which had cumulative effects over time.

Insights into the Mechanism of Proliferation on the Special Microbes Mediated by Phenolic Acids in the Rhizosphere under Continuous Monoculture Regimes.

As potent allelochemicals, phenolic acids are believed to be associated with replanting disease and cause microflora shift and structural disorder in the rhizosphere soil of continuously monocultured . The transcriptome sequencing was used to reveal the mechanisms underlying the differential response of pathogenic bacterium and beneficial bacterium on their interactions with phenolic acids, the main allelochemicals in root exudates of in the monoculture system. The microbes were inoculated in the pots containing soil and the medicinal plant in this study.

Silver-promoted (radio)fluorination of unsaturated carbamates via a radical process.

The intramolecular fluorocyclization of unsaturated carbamates is described here using a hypervalent iodine reagent in the presence of a silver catalyst. Both (hetero)aryl-substituted olefins and acrylamides can be utilized as effective substrates. Preliminary mechanistic investigations suggest that the reaction proceeds via a cyclization/1,2-(hetero)aryl migration/fluorination cascade involving an unusual radical process.

Insights into the Regulation of Rhizosphere Bacterial Communities by Application of Bio-organic Fertilizer in Monoculture Regime.

The biomass and quality of suffers a significant decline under monoculture. Since rhizosphere miobiome plays crucial roles in soil health, deep pyrosequencing combined with qPCR was applied to characterize the composition and structure of soil bacterial community under monoculture and different amendments. The results showed compared with the 1st-year planted (FP), 2nd-year monoculture of (SP) led to a significant decline in yield and resulted in a significant increase in but a decline in spp.

High-Valent Palladium-Promoted Formal Wagner-Meerwein Rearrangement.

An oxy-palladation, formal Wagner-Meerwein rearrangement and fluorination cascade has been established for generating fluorinated oxazolidine-2,4-diones and oxazolidin-2-ones. The reaction has a broad substrate scope in which both aryl and alkyl groups can be utilized as efficient migrating groups. Experimental evidence suggests that the reaction is initiated by anti-oxy-palladation of the olefin, followed by oxidative generation of an alkyl Pd intermediate and a concerted migration-fluorination.