Differential benefits of arbuscular mycorrhizal and ectomycorrhizal infection of Salix repens

Ectomycorrhizal (EcM) and arbuscular mycorrhizal (AM) associations of Salix repens were studied at 16 sites in different successional stages of dune ecosystems (calcareous-acidic, dry-wet) in the Netherlands. High EcM colonization, low AM colonization, and lack of differences between habitats indicate that ectomycorrhizas do not increase their importance in later successional stages. EcM and AM colonization and plant-nutrient status indicate that the relative importance of P and N does not change during succession, but during seasons. Salix repens showed low levels of AM colonization but, nevertheless, even these low levels contributed to covering the P demands of the plant. As a decrease in AM colonization in S. repens at the end of the season coincided with a decrease in AM inoculum potential, the seasonal decline of arbuscular mycorrhiza is caused by changes in plant demand or soil nutrient availability rather than by interference by ectomycorrhiza. Regardless of seasonal shifts and possible interaction between ectomycorrhiza and arbuscular mycorrhiza, both persist in the plant roots during seasons and throughout succession. Differences in the habitat preference of various EcM morphotypes and arbuscular mycorrhiza suggest that mycorrhizal diversity contributes to the broad ecological amplitude of S. repens.

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Simulated mammal browsing and host gender effects on dual mycorrhizal Salix repens

Botany ◽

10.1139/b10-081 ◽

2011 ◽

Vol 89 (1) ◽

pp. 35-42 ◽

Cited By ~ 6

Author(s):

Karita Saravesi ◽

Annamari Markkola ◽

Pasi Rautio ◽

Juha Tuomi

Keyword(s):

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Gender Effects ◽

Dioecious Plants ◽

Carbon Availability ◽

Reproduction Costs ◽

Ecm Fungi ◽

Lower Biomass ◽

Salix Repens ◽

Simulated Browsing

We studied effects of simulated browsing and host plant gender on mycorrhizal status of dioecious Salix repens, forming both ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) symbioses. Owing to their lower biomass production, AM fungi may require less carbon from the host and have a competitive advantage over ECM fungi when carbon availability is reduced. Further, in dioecious plants, females have generally higher reproduction costs than males. Hence, herbivory may be especially detrimental to female plants and their ECM symbionts in favour of AM symbionts. Fifty percent shoot clipping increased the number of vegetative shoots but reduced the proportion of flowering shoots equally in male and female hosts. Despite clipping, ECM and AM colonization remained unchanged. However, slightly reduced soil fungal biomass was found in clipped patches of male S. repens. Our novel finding of AM spores occurring in the ECM fungal mantle of S. repens roots suggests that both mycorrhizal partners may coexist in the same root segment. Since no interaction between gender and clipping in fungal parameters was detected, we conclude that female and male S. repens are equally preferable hosts for fungal symbionts, even when carbohydrate availability has been decreased because of herbivory.

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Alleviation of salt stress by arbuscular-mycorrhizal Glomus species in Lactuca sativa plants

Physiologia Plantarum ◽

10.1034/j.1399-3054.1996.980413.x ◽

1996 ◽

Vol 98 (4) ◽

pp. 767-772 ◽

Cited By ~ 4

Author(s):

J. M. Ruiz-Lozano ◽

R. Azcon ◽

M. Gomez

Keyword(s):

Salt Stress ◽

Lactuca Sativa ◽

Arbuscular Mycorrhizal ◽

Glomus Species

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Experimentally altered rainfall regimes and host root traits affect grassland arbuscular mycorrhizal fungal communities

10.32942/osf.io/cu4jh ◽

2019 ◽

Author(s):

Coline Deveautour ◽

Suzanne Donn ◽

Sally Power ◽

Kirk Barnett ◽

Jeff Powell

Keyword(s):

Fungal Community ◽

Community Assembly ◽

Root Length ◽

Specific Root Length ◽

Root Traits ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Rainfall Regime ◽

Precipitation Regimes ◽

Rainfall Regimes

Future climate scenarios predict changes in rainfall regimes. These changes are expected to affect plants via effects on the expression of root traits associated with water and nutrient uptake. Associated microorganisms may also respond to these new precipitation regimes, either directly in response to changes in the soil environment or indirectly in response to altered root trait expression. We characterised arbuscular mycorrhizal (AM) fungal communities in an Australian grassland exposed to experimentally altered rainfall regimes. We used Illumina sequencing to assess the responses of AM fungal communities associated with four plant species sampled in different watering treatments and evaluated the extent to which shifts were associated with changes in root traits. We observed that altered rainfall regimes affected the composition but not the richness of the AM fungal communities, and we found distinctive communities in the increased rainfall treatment. We found no evidence of altered rainfall regime effects via changes in host physiology because none of the studied traits were affected by changes in rainfall. However, specific root length was observed to correlate with AM fungal richness, while concentrations of phosphorus and calcium in root tissue and the proportion of root length allocated to fine roots were correlated to community composition. Our study provides evidence that climate change and its effects on rainfall may influence AM fungal community assembly, as do plant traits related to plant nutrition and water uptake. We did not find evidence that host responses to altered rainfall drive AM fungal community assembly in this grassland ecosystem.

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Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

10.32942/osf.io/t82ug ◽

2019 ◽

Cited By ~ 1

Author(s):

Coline Deveautour ◽

Sally Power ◽

Kirk Barnett ◽

Raul Ochoa-Hueso ◽

Suzanne Donn ◽

...

Keyword(s):

Community Composition ◽

Plant Community ◽

Plant Communities ◽

Fungal Community ◽

Mycorrhizal Fungi ◽

Temporal Dynamics ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Plant Responses ◽

Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

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