Biochar inhibits ginseng root rot pathogens and increases soil microbiome diversity

Understanding the effects of organic pasture management on the soil microbiome is important for sustainable forage production since soil microbiome diversity contributes to improved nutrient cycling, soil structure, plant growth, and environmental resiliency; however, the soil microbiome response to pasture management is largely unknown. This study assessed the soil microbial diversity, richness, and community structure following 10 years of pasture management (organic or non-organic) of the V4 region of the 16S rRNA using the Illumina MiSeq platform. Soil samples were collected from 0–15 cm in July and August from 2017–2018 and soil nutrient properties (nutrients, carbon, nitrogen, and pH) quantified and correlated with soil microbial diversity. Overall, greater soil bacterial species richness (P ≤ 0.05) occurred in organic relative to non-organic (conventional) systems. Management affected bacterial species richness (Chao1), with greater richness occurring in organic pasture soils and less richness occurring in non-organic systems (P ≤ 0.05). Similarly, management affected bacterial evenness (Simpson’s index), with a more diverse community occurring in organically managed soils relative to non-organic pastures (P ≤ 0.05). Linear discriminant analysis effect size analysis showed statistically significant and biologically consistent differences in bacterial taxa in organic compared with non-organic soils. Therefore, there was a shift in bacterial community structure in organic relative to non-organic soils (P ≤ 0.05). Additionally, soil nutrients (Fe, Mg, Ni, S, Al, K, Cd, and Cu), pH, C, and N were correlated with one or more dominant bacterial phyla (Gemmatimonadetes, Planctomycetes, Firmicutes, Chloroflexi, Actinobacteria, and Acidobacteria). Overall, pasture management affected soil microbial diversity, with greater diversity occurring in organic than non-organic systems, likely owing to applications of organic poultry litter in organic systems compared to non-organic management (use of inorganic-fertilizers and herbicides). Results indicate that when pastures are converted to organic production systems, soil microbial richness and diversity may increase, thereby resulting in enhanced soil microbiome diversity and overall ecosystem services.

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Fungal-bacterial diversity and microbiome complexity predict ecosystem functioning

Nature Communications ◽

10.1038/s41467-019-12798-y ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 67

Author(s):

Cameron Wagg ◽

Klaus Schlaeppi ◽

Samiran Banerjee ◽

Eiko E. Kuramae ◽

Marcel G. A. van der Heijden

Keyword(s):

Microbial Communities ◽

Bacterial Communities ◽

Ecosystem Functioning ◽

Microbial Interactions ◽

Soil Microbiome ◽

Ecosystem Functions ◽

Microbial Network ◽

Grassland Ecosystems ◽

Microbiome Diversity ◽

Ecological Associations

Abstract The soil microbiome is highly diverse and comprises up to one quarter of Earth’s diversity. Yet, how such a diverse and functionally complex microbiome influences ecosystem functioning remains unclear. Here we manipulated the soil microbiome in experimental grassland ecosystems and observed that microbiome diversity and microbial network complexity positively influenced multiple ecosystem functions related to nutrient cycling (e.g. multifunctionality). Grassland microcosms with poorly developed microbial networks and reduced microbial richness had the lowest multifunctionality due to fewer taxa present that support the same function (redundancy) and lower diversity of taxa that support different functions (reduced functional uniqueness). Moreover, different microbial taxa explained different ecosystem functions pointing to the significance of functional diversity in microbial communities. These findings indicate the importance of microbial interactions within and among fungal and bacterial communities for enhancing ecosystem performance and demonstrate that the extinction of complex ecological associations belowground can impair ecosystem functioning.

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Cylindrocarpon destructans/Ilyonectria radicicola-species complex: Causative agent of ginseng root-rot disease and rusty symptoms

Journal of Ginseng Research ◽

10.1016/j.jgr.2017.01.004 ◽

2018 ◽

Vol 42 (1) ◽

pp. 9-15 ◽

Cited By ~ 22

Author(s):

Mohamed El-Agamy Farh ◽

Yeon-Ju Kim ◽

Yu-Jin Kim ◽

Deok-Chun Yang

Keyword(s):

Causative Agent ◽

Root Rot ◽

Species Complex ◽

Ginseng Root ◽

Cylindrocarpon Destructans ◽

Root Rot Disease ◽

Rot Disease

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American Ginseng Root Rot Caused by Fusarium redolens in China

Plant Disease ◽

10.1094/pdis-12-20-2600-pdn ◽

2021 ◽

Author(s):

Sanhong Fan ◽

Fangjie Zhao ◽

Jiguang Zhang ◽

Wenjing Shang ◽

Xiaoping Hu

Keyword(s):

Root Rot ◽

Vascular Tissue ◽

Morphological Characteristics ◽

American Ginseng ◽

Shaanxi Province ◽

Ginseng Root ◽

Continuous Cropping ◽

Sterile Water ◽

Fusarium Spp ◽

Fusarium Redolens

American ginseng (Panax quinquefolium L.) originating from North America is one of important herbal medicine and economic crops . With the increasing market demand, China has become the third producer and the largest consumer country of American ginseng. However, continuous cropping obstacle has become the most serious problem for the production of American ginseng, and the continuous cropping of soils usually lead to accumulations of root fungal pathogens and increasing plant disease occurrence (1), root rot caused by the notorious soil-borne pathogenic fungi, Fusarium spp., results in a significant reduction of yield and quality of American ginseng. Investigation of American ginseng root rot was carried out in Liuba county, Shaanxi province, China from 2017 to 2019. About 20% of over 3-year-old American ginseng showed varied root rot symptoms in newly reclaimed fields, and more than 70% in continuous American ginseng planting fields. Among these root rot diseases, we found one kind of disease which shows symptoms of red leaves in initial stage and yellow or yellow brown lesions at the reed heads or taproots. The lesions mainly appear on the root surface; however, the vascular tissue has no discoloration. The aboveground parts become wilted and died, and the whole root appears dark brown rots. Fifteen Fusarium spp. isolates were obtained by cutting diseased rot roots into 5 × 5 mm2 pieces, disinfecting in 70% ethanol for 1 min, rinsing 2 ~ 3 times in sterile water for 1 min and isolating on PDA medium including 50 μg/mL streptomycin sulfate. All the isolates have identical morphological characteristics. The colony was white with curved and uplifted aerial hyphae in central region. The colony diameter was 48 ~51 mm after 6 days at room temperature. Microconidia were oval to cylindrical shape with 0 to 1 septa, ranged from 6.24 to10.09 μm long; the macroconidia were fusiform to conical with a hooked apical cell and a foot-shaped basal cell, usually 3 to 5 septa, ranged from 31.45 to 42.52 μm long. The chlamydospores were not found under our culture condition. Preliminary data analysis showed that the morphological characteristics of these isolates were consistent with the descriptions of Fusarium redolens (2). To clarify the fungus in the taxonomy , the rDNA internal transcribed spacer (ITS), the translation elongation factor 1 alpha (TEF1-α) and the RNA polymerase II subunit 1 (RPB1) fragments of two randomly selected isolates were amplified and sequenced. The sequences of the corresponding fragments of the two isolates were identical. The blast results in the GenBank and FUSARIUM-ID databases show the isolates belong to F. redolens (3). Previous study indicated F. redolens has an indistinguishable relative, F. hostae (4). Although the ITS sequence (MW331695) cannot provide enough information to distinguish them, the phylogenetic tree combined the sequence of TEF1-α (tempID: 2407237 ) and RPB1 (tempID: 2407229) clearly showed that the isolates are F. redolens. (Fig) The pathogenicity of a representative isolate, YP04, was tested on ginseng taproot by in vivo inoculation experiments with three replications. The taproot surface of 2-year-old healthy ginseng was washed and disinfested with 75% alcohol for 1 min and rinsed with sterile water, and dried. The surface of taproot was injured with sterilized steel needles and immersed in 1 × 106 /ml spore suspension (sterile water for control plants) for 30 min. The treatment and control plants were transplanted in 20 cm diameter flowerpots filled with sterilized humus and cultured in a greenhouse at 18-23°C. Six days after transplanting, the leaves began to turn red. The cortex of ginseng taproot showed yellow brown lesions and the vascular tissue turn to light yellow. Fifteen days after transplanting, the aboveground parts of treatment plants began to wilting and the taproots showed serious rots. no taproot rot was observed in the controls. The pathogen was re-isolated from the diseased taproots successfully. To our knowledge, this is the first report of F. redolens causing root rot of American ginseng in China.

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Microbiome Aggregated Traits and Assembly Are More Sensitive to Soil Management than Diversity

mSystems ◽

10.1128/msystems.01056-20 ◽

2021 ◽

Author(s):

Andrew L. Neal ◽

David Hughes ◽

Ian M. Clark ◽

Janet K. Jansson ◽

Penny R. Hirsch

Keyword(s):

Land Management ◽

Soil Management ◽

Soil Microbiome ◽

Environmental Services ◽

Clean Water ◽

Long Term Effects ◽

Microbiome Diversity ◽

Management Approaches ◽

And Function

Changes in soil microbiome diversity and function brought about by land management are predicted to influence a range of environmental services provided by soil, including provision of food and clean water. However, opportunities to compare the long-term effects of combinations of stresses imposed by different management approaches are limited.

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Biocontrol Efficacies of Bacillus Species Against Cylindrocarpon destructans Causing Ginseng Root Rot

The Plant Pathology Journal ◽

10.5423/ppj.2011.27.4.333 ◽

2011 ◽

Vol 27 (4) ◽

pp. 333-341 ◽

Cited By ~ 23

Author(s):

Ye-Lim Jang ◽

Sang-Gyu Kim ◽

Young-Ho Kim

Keyword(s):

Root Rot ◽

Ginseng Root ◽

Bacillus Species ◽

Cylindrocarpon Destructans

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Silicon confers protective effect against ginseng root rot by regulating sugar efflux into apoplast

Scientific Reports ◽

10.1038/s41598-019-54678-x ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Ragavendran Abbai ◽

Yu-Jin Kim ◽

Padmanaban Mohanan ◽

Mohamed El-Agamy Farh ◽

Ramya Mathiyalagan ◽

...

Keyword(s):

Protective Effect ◽

Root Rot ◽

Molecular Basis ◽

Severity Index ◽

Protective Role ◽

Ginseng Root ◽

Term Analysis ◽

Root Quality

AbstractRoot rot caused by Ilyonectria mors-panacis is a devastating fungal disease leading to defect in root quality and causes reduced yield during the perennial life cycle of Panax ginseng Meyer. This indicates the imperative need to understand the molecular basis of disease development and also to enhance tolerance against the fungus. With this idea, the protective effect of silicon (supplied as silica nanoparticles) in P. ginseng root rot pathosystem and its molecular mechanism was investigated in the current study. We have tested different concentrations of silicon (Si) to disease-infected ginseng and found that long term analysis (30 dpi) displayed a striking 50% reduction in disease severity index upon the treatment of Si. Expectedly, Si had no direct degradative effect against the pathogen. Instead, in infected roots it resulted in reduced expression of PgSWEET leading to regulated sugar efflux into apoplast and enhanced tolerance against I. mors-panacis. In addition, under diseased condition, both protopanaxadiol (PPD) and protopanaxatriol (PPT) type ginsenoside profile in roots were higher in Si treated plants. This is the first report indicating the protective role of Si in ginseng-root rot pathosystem, thereby uncovering novel features of ginseng mineral physiology and at the same time, enabling its usage to overcome root rot.

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