Lineage-Specific Genes and Cryptic Sex: Parallels and Differences between Arbuscular Mycorrhizal Fungi and Fungal Pathogens

Gaeumannomyces graminis var. tritici causes take-all disease, the most important root disease of cereal plants. Cereal plants are able to form a symbiotic association with soil-borne arbuscular mycorrhizal fungi which can provide bioprotection against soil-borne fungal pathogens. However, the bioprotective effect of arbuscular mycorrhizal fungi against soil-borne fungal pathogens might vary. In the present study we tested the systemic bioprotective effect of the arbuscular mycorrhizal fungi Glomus mosseae, Glomus intraradices and Gigaspora rosea against the soil-borne fungal pathogen Gaeumannomyces graminis var. tritici in a barley split-root system. Glomus intraradices, Glomus mosseae and Gigaspora rosea colonized the split-root system of barley plants at different levels; however, all arbuscular mycorrhizal fungi clearly reduced the level of root lesions due to the pathogen Gaeumannomyces graminis. Our data indicate that some arbuscular mycorrhizal fungi need high root colonization rates to protect plants against fungal pathogens, whereas others act already at low root colonization rates.    

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Meta-Analysis of Interactions between Arbuscular Mycorrhizal Fungi and Biotic Stressors of Plants

The Scientific World JOURNAL ◽

10.1155/2014/746506 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Haishui Yang ◽

Yajun Dai ◽

Xiaohua Wang ◽

Qian Zhang ◽

Liqun Zhu ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Fungal Pathogens ◽

Competitive Inhibition ◽

Meta Analysis ◽

Arbuscular Mycorrhizal ◽

Reciprocal Inhibition ◽

Plant Tolerance ◽

Negative Effects ◽

Positive Effects

Naturally, simultaneous interactions occurred among plants, herbivores, and soil biota, that is, arbuscular mycorrhizal fungi (AMF), nematodes, and fungal pathogens. These multiple interactions play fundamental roles in driving process, structure, and functioning of ecosystems. In this study, we conducted a meta-analysis with 144 papers to investigate the interactions between AMF and plant biotic stressors and their effects on plant growth performance. We found that AMF enhanced plant tolerance to herbivores, nematodes, and fungal pathogens. We also found reciprocal inhibition between AMF and nematodes as well as fungal pathogens, but unidirectional inhibition for AMF on herbivores. Negative effects of AMF on biotic stressors of plants depended on herbivore feeding sites and actioning modes of fungal pathogens. More performance was reduced in root-feeding than in shoot-feeding herbivores and in rotting- than in wilt-fungal pathogens. However, no difference was found for AMF negative effects between migratory and sedentary nematodes. In return, nematodes and fungal pathogens generated more reduction of root colonization in Non-Glomeraceae than in Glomeraceae. Our results suggested that AMF positive effects on plants might be indirectly mediated by competitive inhibition with biotic stressors of plants. These positive and negative interactions make potential contributions to maintaining ecosystem stability and functioning.

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