Interactions of ericoid mycorrhizal fungi and root pathogens in Rhododendron: &lt;I&gt;In vitro&lt;/I&gt; tests with plantlets in sterile liquid culture

Tang

et al. 2016

Sci Rep

Ericoid mycorrhiza (ERM) are expected to facilitate establishment of ericaceous plants in harsh habitats. However, diversity and driving factors of the root-associated fungi of ericaceous plants are poorly understood. In this study, hair-root samples of Vaccinium carlesii were taken from four forest types: old growth forests (OGF), secondary forests with once or twice cutting (SEC I and SEC II), and Cunninghamia lanceolata plantation (PLF). Fungal communities were determined using high-throughput sequencing, and impacts of human disturbances and the intra- and inter-annual variability of root-associated fungal community were evaluated. Diverse fungal taxa were observed and our results showed that (1) Intra- and inter-annual changes in root-associated fungal community were found, and the Basidiomycota to Ascomycota ratio was related to mean temperature of the sampling month; (2) Human disturbances significantly affected structure of root-associated fungal community of V. carlesii, and two secondary forest types were similar in root-associated fungal community and were closer to that of the old growth forest; (3) Plant community composition, edaphic parameters, and geographic factors significantly affected root-associated fungal communities of V. carlesii. These results may be helpful in better understanding the maintenance mechanisms of fungal diversity associated with hair roots of ERM plants under human disturbances.

Section: Discussionmentioning

confidence: 85%

Root-associated fungi of Vaccinium carlesii in subtropical forests of China: intra- and inter-annual variability and impacts of human disturbances

Tang

et al. 2016

Sci Rep

“…Pisolithus tinctorius strain SMF, an ectomycorrhizal fungus, strongly inhibited the growth of V. dahliae [ 75 ]. Ericoid mycorrhizal fungi could protect the host plants from infections by pathogens such as Phytophthora cinnamomi and Pythium when they were sufficiently present in or on the roots [ 76 ]. Hage-Ahmed et al demonstrated that a direct antibiotic activity of root exudates from tomatoes towards F. oxysporum f.sp.…”

Section: Discussionmentioning

confidence: 99%

Improvement of Verticillium Wilt Resistance by Applying Arbuscular Mycorrhizal Fungi to a Cotton Variety with High Symbiotic Efficiency under Field Conditions

Gao

Ren

et al. 2018

IJMS

Arbuscular mycorrhizal fungi (AMF) play an important role in nutrient cycling processes and plant stress resistance. To evaluate the effect of Rhizophagus irregularis CD1 on plant growth promotion (PGP) and Verticillium wilt disease, the symbiotic efficiency of AMF (SEA) was first investigated over a range of 3% to 94% in 17 cotton varieties. The high-SEA subgroup had significant PGP effects in a greenhouse. From these results, the highest-SEA variety of Lumian 1 was selected for a two-year field assay. Consistent with the performance from the greenhouse, the AMF-mediated PGP of Lumian 1 also produced significant results, including an increased plant height, stem diameter, number of petioles, and phosphorus content. Compared with the mock treatment, AMF colonization obviously inhibited the symptom development of Verticillium dahliae and more strongly elevated the expression of pathogenesis-related genes and lignin synthesis-related genes. These results suggest that AMF colonization could lead to the mycorrhiza-induced resistance (MIR) of Lumian 1 to V. dahliae. Interestingly, our results indicated that the AMF endosymbiont could directly inhibit the growth of phytopathogenic fungi including V. dahliae by releasing undefined volatiles. In summary, our results suggest that stronger effects of AMF application result from the high-SEA.

“…Lecanicillium (Zare and Gams 2001;Cho et al 2003;Heitman et al 2010;Pathrose et al 2014). The much pathogenic indicators in PLF may be due to the relatively lower ERM colonization in PLF, since extensive ERM colonization could enhance pathogen resistance of plants (Grunewaldt-Stöcker et al 2013). We should also notice that these putative pathogens (i.e.…”

Section: R a F Tmentioning

confidence: 99%

The effects of different human disturbance regimes on root fungal diversity ofRhododendron ovatumin subtropical forests of China

Tang

et al. 2017

Can. J. For. Res.

Ericoid mycorrhizal associations are a symbiotic relationship between soil fungi and ericaceous plants. Diversity of fungi associated with hair roots of ericaceous plants may vary as a result of frequent disturbances by human activities. The fungal diversity and communities associated with hair roots of Rhododendron ovatum were investigated along a human disturbance gradient in subtropical forests of China. Nine hundred fungal operational taxonomic units were determined by high-throughput sequencing, including different phyla such as Ascomycota, Basidiomycota, Zygomycota, Chytridiomycota, and Glomeromycota. The dominant phylum in Cunninghamia lanceolata plantations and old-growth forest was Ascomycota, while Basidiomycota was the dominant phylum in secondary forests. The indicator species analyses showed that more pathogenic indicator fungi appeared in the disturbed forests, whereas more putative ericoid mycorrhizal fungi existed in the old-growth forests. Principal component analysis also showed that the fungal communities in the hair roots of R. ovatum were distinct between natural forests and plantations, suggesting that the fungal communities associated with hair roots of R. ovatum after logging were resilient and could recover to predisturbance status. The results of envfit analysis showed that performance of host plants rather than accompanying plant community and soil parameters of plots was the key determinant of the root-associated fungal community of R. ovatum.