Root rot disease is vital disease of Coptis chinensis, it has bursted in most producing area in recent years, and has caused severe damage. To identify the pathogenic fungi, Fusarium spp. fungi were isolated from rot root, of which the pathogenic fungi were screened with inoculation on C. chinensis root and plant, and identified with molecular and morphological method. The 20 Fusarium spp. fungi were obtained, of which 5 displayed high pathogenicity. It was deduced that F. oxysporum, F. solani and F. tricinctum were the pathogen, possibly pioneer pathogen of C. chinensis root rot disease. Among which F. oxysporum was dominant and deserved to pay more attention. High temperature and high humidity can increase pathogenicity of Fusarium spp. So the global climate warming may lead to temperature rising of C. chinensis producing area and favor the pathogen fungi, which may be one of the main factors leading to bursting of C. chinensis root rot disease. To control the root rot, beside developing and using pesticide, producing base should be moved to a high altitude area.
Coptis/microbiology* ; Fusarium/pathogenicity* ; Plant Diseases/microbiology* ; Plant Roots/microbiology*

Rhizosphere is the main place for the communication between medicinal plants and rhizosphere microorganisms. Medicinal plants are closely related to the diversity and richness of rhizosphere microorganisms, and rhizosphere microorganisms in the rhizosphere of medicinal plants have important effects on the growth and development, yield, quality and resilience of medicinal plants. The reasonable and effective utilization of the principle of interaction between medicinal plants and rhizosphere microorganisms has practical guiding significance for promoting the growth of medicinal plants, enhancing the ability of resistance to diseases and resisting the invasion of pathogens. This paper reviewed the research status of medicinal plants and rhizosphere microorganisms in recent years, including the influence of medicinal plants on rhizosphere microorganisms, the influence of rhizosphere microorganisms on medicinal plants and the mechanism of interaction between medicinal plants and rhizosphere microorganisms. The problems existing in the study of medicinal plants and rhizosphere microorganisms and the direction for further study were also pointed out.
Plant Roots ; Plants, Medicinal ; Rhizosphere ; Soil Microbiology

In this study, Paeonia suffruticosa roots and rhizospheric soil in five geographic regions which were harvested in October were utilized as experimental materials, then the diversity of endophytic and rhizospheric actinomycetes were investigated by High-throughput sequencing technique. The 1 754 operational taxonomic units (OTUs) were obtained from 129 954 high quality sequences, 1 311 OTUs were detected in rhizospheric actinomycetes and belonged to four classes, four orders, twenty-seven families and ninety-seven genera, thirty-three genera such as Ilumatobacter were found in the five regions rhizospheric soil while three genera such as Longispora were only detected in the Dao-di regions, the dominant genera were Mycobacterium, Nocardioides, Streptomyces. 443 OTUs were obtained in roots and distributed in three classes, three orders, twenty-four families and fifty genera, thirteen genera such as Cryptosporangium were found in the five regions roots while Planosporangium, Luteococcus were only detected in the Dao-di regions, the dominant genera were Nocardioides. Alpha diversity analysis showed that the Shannon and Chao1 index in rhizospheric actinomycetes in Bozhou, Tongling and Nanling region were higher than Heze and Luoyang. Based on principal co-ordinates analysis (PCoA) analysis, the rhizospheric actinomycetes formations were similar in Tongling and Nanling region, at the same in Tongling and Luoyang endophytic actinomycetes. According to heatmap analysis, Bozhou, Tongling and Nanling region rhizospheric actinomycetes showed a close similarity in actinomycetes community structures on phylogenetic analysis, while Tongling, Luoyang and Nanling endophytic actinomycetes showed the same. Our results not only suggested that the rich and diverse actinomycetes resources in P. suffruticosa roots and rhizospheric soil but also revealed rhizospheric actinomycetes in the Dao-di regions had high similarity.
Actinobacteria ; Paeonia ; Phylogeny ; Plant Roots ; Soil Microbiology

OBJECTIVETo study the root microstructure and the distribution of the endophytic fungi in Taxus chinensis var. mairei.

METHODSThe roots of Taxus chinensis var. mairei at nature were cut with paraffin, dyed and observed by microscope.

RESULTSThe secondary structure of the roots of Taxus chinensis var. mairei consisted of the periderm and vascular cylinder (stele). Axial and radial systems formed the secondary xylem of the roots. Tracheids and xylary parenchyma cells constituted the axial system, and xylary radial formed the radial systems. The secondary phloem consisted of sieve cells and phloem parenchymas. Only a small quantity of phloem fibers were distributed in the secondary phloem, and the phloem ray was unconspicuous. Many endophytic mycelia penetrated in the velamina.

CONCLUSIONSThe secondary structure of the root of Taxus chinensis var. mairei accords with that of other gymnosperms and dicotyledons, although its secondary xylem is constituted with tracheids and sieve cells. The endophytic mycelia exists in the local cells of velamina in the roots of Taxus chinensis var. mairei.

Fungi ; isolation & purification ; Plant Roots ; microbiology ; ultrastructure ; Taxus ; microbiology ; ultrastructure

OBJECTIVETo investigate the arbuscular mycorrhizal (AM) fungi resources in rhizosphere of Chaenomeles speciosa in Xuancheng, Anhui province.

METHODRoots were stained with acid fuchsin and then mounted and observed under a microscope; Spores were extracted from the rhizosphere soil using wet-sieving method.

RESULTC. speciosa could be colonized and formed typical arbuscular mycorrhizas with AM fingi. 18 species of arbuscular mycorrhizal fungi were identified, belonging to four genera, 11 species of Glomus, 3 species of Acaulospora, 3 species of Scutellospora and 1 species of Entrophospora. Glomus were the dominant AM fungi in the rhizosphere.

CONCLUSIONThe resources of AM fungi in rhiszophere of C. speciosa were very abundant. Fungi from Glomus were possible the dominant AMF in the rhizosphere.

China ; Mycorrhizae ; classification ; Plant Roots ; microbiology ; Rosaceae ; microbiology

UNLABELLEDTo study the infected root of Panax quinquefolium on the contents of ginsenosides.

METHODThe contents of three major ginsenosides Rg1, Re and Rb1 were determined by HPLC compared quantitatively between the different degree infected roots and normal root in the phloem and xylem.

RESULTRg1 in phloem and xylem of varying degrees infected root showed no significant difference, but Rb1 decreased 26.3% and 28.3% respectively in medium and serious infected roots comparing to normal root. Re in phloem of seriously infected roots decreased in xylem significantly.

CONCLUSIONThe results indicate that the variation of ginsenosides in different degrees infected roots exists and the proportion of Rg1, Re and Rb1 in the total ginsenosides changes.

Ginsenosides ; chemistry ; Panax ; chemistry ; microbiology ; Plant Diseases ; microbiology ; Plant Roots ; chemistry ; microbiology

The Astragalus membranaceus root rot disease,a soil-borne disease,has become increasingly severe in Shanxi province.This study was aimed at getting antagonistic Bacillus with excellent bio-control effects,and determining its effects on bacterial communities in root zone soil. With Fusarium solani and F. acuminatum as the target,antagonistic Bacillus was selected through such tests as living body dual culture,antifungal effect of bacteria-free filtrate,mycelia growth inhibition in vitro and control effect in detached roots,and identified with morphology,physio-biochemical characteristics and 16 S r DNA sequence analysis. The results showed that the Bacillus strain SXKF16-1 had obvious antifungal effect. The diameter of inhibition zone of its bacteria-free filtrate to F. solani and F. acuminatum was( 25. 90±1. 18) mm and( 25. 86±1. 85) mm respectively,and showed a lasting inhibition effect to mycelia growth. The disease index of the protective treatment and that of the cure treatment in detached roots test to F. solani and F. acuminatum were( 37. 50±8. 58),( 41. 67±4. 90) and( 25. 00±8. 33),( 38. 89±9. 62) respectively,both being significantly different( P<0. 05) from that of the control. The strain SXKF16-1 was identified as Bacillus atrophaeus. The B. atrophaeus SXKF16-1 showed significantly inhibition effect to pathogen causing root rot and could increase the bacterial diversity in root zone soil. It has potential to be developed as a special biocontrol agent.
Astragalus Plant/microbiology* ; Bacillus/physiology* ; Biological Control Agents ; Fusarium/pathogenicity* ; Plant Diseases/prevention & control* ; Plant Roots/microbiology* ; Soil Microbiology

In this study, the colonization, diversity and relative abundance of arbuscular mycorrhizal fungi(AMF) in the roots of Panax quinquefolius in different habitats of Shandong province were analyzed by staining-microscopy and high-throughput sequencing. The data were analyzed by bioinformatics tools and statistical software. The results showed that the roots of P. quinquefolius in different habitats were colonized by AMF with different rates and intensities. The AMF in roots of P. quinquefolius belong to three genera, three families, three orders, one class and one phylum. At the level of order, the AMF mainly included Paraglomerales(52.48%), Glomerales(25.60%) and Archaeosporales(3.08%). At the level of family, the AMF were dominated by Paraglomeraceae(52.48%), Glomeraceae(18.94%) and Claroideoglomeraceae(3.05%). At the level of genus, Paraglomus(51.46%), Glomus(20.01%) and Claroideoglomus(3.52%) accounted for a large proportion, of which Paraglomus and Glomus were dominant. Cluster analysis showed that the AMF in roots of P. quinquefolius with close geographical locations could be clustered together. In this study, the diversity and dominant germplasm resources of AMF in roots of P. quinquefolius cultivated in the main producing areas were identified, which provi-ded basic data for revealing the quality formation mechanism of P. quinquefolius medicinal materials from the perspective of environment.
Fungi ; Glomeromycota ; Humans ; Mycorrhizae/genetics* ; Panax ; Plant Roots ; Soil Microbiology

This study is aimed to reveal the rhizosphere soil fungal community structure difference of Coptis chinensis cropping between natural forest and artificial shed modes, and provide theoretical guidance for soil improvement and C. chinensis planting. The rhizosphere soil samples of 1-5-year-old C. chinensis under natural forest and artificial shed modes were collected. Illumina high-throughput sequencing technology was used to analyze the community structure and diversity of soil fungi under the tow cropping modes,and the effects of soil nutriment indices on soil fungal community structure. The results suggested that the abundance and diversity of fungal communities in soil of 2-5-year-old C. chinensis were not significant different in both two cropping modes, but it was significantly higher than that in the 1-year-old C. chinensis. Comparing soil samples from the same year-old C. chinensis under the two cropping modes, it was found that there was no significant difference in the abundance and diversity of fungal communities. The fungal community of the rhizosphere soil was different in composition and abundance between tow cropping modes, and between different planting years. The 17 phyla,59 classes and 155 orders,and 17 phyla,59 classes and 157 orders were detected in the rhizosphere soil of C. chinensis under the cropping modes of natural forest and the artificial shed, respectively. Ascomycota, Basidiomycota and Mortierellomycota were dominant phyla in rhizosphere soil, and the average abundance of the 3 phyla accounted for 74.36% and 74.30% of the total fungi. The results of analysis of similarities showed that there were significant differences in the fungal community structure of 1-year-old and 2-year-old C. chinensis soil fungi, and there was no significant difference in the community structure of 3-5-year-old samples. Under the natural forest cropping mode, there were significant differences among the samples of different years. Under the artificial shed cropping, there were significant differences in fungal community structure between 1-year-old and 3-5-year-old C. chinensis soil, and between 2-year-old and 3-5-year-old C. chinensis soil. The results of canonical correlation analysis showed that soil pH and soil organic matter content were the main factors affecting the soil fungal community structure. Soil organic matter content was positively correlated with Basidiomycota and Cryptomycota, pH was negatively correlated with Basidiomycota and C. ryptomycota. The planting of C. chinensis has promoted the diversity and abundance of rhizosphere fungal community significantly. For the same year-old C. chinensis soil, abundance of fungal community was no significant difference between two cropping modes. There are significant differences in the rhizosphere soil fungal community structure between tow cropping modes in the first two years of planting. Through the interaction between the rhizosphere and the soil and the continuous selection of the rhizosphere to the fungal community, the fungal community structure tended to be the same between the two cropping modes in rhizosphere soil of 3-5-year old C. chinensis. The soil pH and orga-nic matter content were the main factors affecting the change of fungal community structure.
Coptis ; Forests ; Fungi ; Mycobiome ; Plant Roots ; Rhizosphere ; Soil ; Soil Microbiology

The interaction of endophytes and host plant is an effective mean to regulate the growth and secondary metabolism of medicinal plants. Here we want to elucidate the effects and mechanism of Phoma herbarum D603 on the root development and tanshinone synthesis in root of Salvia miltiorrhiza by endophyte-plant coculture system. The mycelium of P. herbarum D603 was colonized in the root tissue space, and formed a stable symbiotic relationship with host plant. The in vitro activities analysis showed that the concentration of IAA produced by D603 can reach(6.45±0.23) μg·mL~(-1), and this strain had some abilities of phosphorus solubilization and siderophore production activities. The coculture experiment showed that strain D603 can significantly promote the synthesis and accumulation of tanshinones in the root of S. miltiorrhiza, in which after 8 weeks of treatment with D603, the content of tanshinone Ⅱ_A in the roots reached up to(1.42±0.59) mg·g~(-1). By the qRT-PCR analysis results, we found that D603 could improve the expression levels of some key genes(DXR, DXS, GGPP, HMGR, CPS) of tanshinone biosynthesis pathway in host plant S. miltiorrhiza, but the promoting effect mainly occurred in the early stage of the interaction, and the enzyme activity level decreased in varying degrees of the later stage. In summary, seed-associated endophyte P. herbarum D603 can promote the growth and root development of S. miltiorrhiza by producing hormones, promoting nutrient absorption and siderophore production, and promote the synthesis and accumulation of tanshinones by regulating the expression level of key genes in the synthetic pathway in S. miltiorrhiza.
Abietanes/biosynthesis* ; Ascomycota/growth & development* ; Endophytes/growth & development* ; Plant Roots/microbiology* ; Salvia miltiorrhiza/microbiology* ; Seeds/microbiology*