Mycorrhizal patterns in depth
Franklin Diggs
SUNY ESF
Review• Mycorrhiza are
symbiotic relationships between plant roots and soil inhabiting fungi
• Plants pass photosynthate to the fungi in return for mineral nutrients, particularly nitrogen and phosphorous
• Formed by most land plants
http://www.keywordpictures.com/keyword/mykorrhiza/
Forests as networks
http://greenlighte.files.wordpress.com/2011/07/alberton-o-kuypert-2009.jpg
Martin Dodge, 2007)
Classification
http://eagle-rock.org/images/thumb/Coupe_mycorhizes.jpg/400px-Coupe_mycorhizes.jpg
http://bioweb.uwlax.edu/bio203/2011/bielmeie_luke/Phylogeny.htm
sporocarp
mantle
Hartig Net vesicle
Why are we interested in depth?
Niche partitioning
Nutrient cycling
Studies in monocultures of dual infection hosts have shown guild wide niche partitioning (Neville et al. 2002)
Arbuscular mycorrhizae are thought to be responsible for phosphate mining, and may be a chief component of phosphorous additions to older plant communities (Smith and Read 2008)
Objectives
• Compare percent root length
colonized in each guild along depth
and the ratio of the two
• Compare the root length of each guild
along depth and the ratio of the two \
Hypotheses
• Percent root length colonized will be less
in the deeper soils than in the shallow in
both guilds, the AM/EM ratio will increase
with depth
• Colonized root length will be less in the
deep soil, but the AM/EM ratio will
increase with depth
Field methods
• Roots were collected by the shoestring crew in
fall 2010
• Shallow soils were collected using 10cm soil cores
• A 20cm power core was used to collect deep soils
• Soils were separated into horizons based on
visual inspection
MethodsRoot length is estimated using grid intersection
Ectomycorrhizal colonization is estimated by using the proportion of those intersections which crossed ectomycorrhizal root tips compared to colonized root
To estimate Arbuscular mycorrhizal percentage <1mm diameter roots are cut into 2mm section and stained, slides are prepared and examined at 400x magnification and the presence or absence of arbuscular mycorrhizal features is noted
Methods
http://mycorrhizas.info/method.html
Results
C5 shallow C5 Deep C7 Shallow C7 Deep0
2
4
6
8
10
12
14
Am Length EM Length Non mycorrhizal length
root
length
cm
/cm
^2 s
oil
Root length per area of soil by mycorrhizal guild
Results
• Greater colonization in shallow soils regardless of
guild (p<0.001)
• Greater root length in shallow soils regardless of
guild (p=0.016)
• No change in the ratio of percent colonization
between guilds across depth (p=0.46)
• Change in the ratio of root length between guilds
across depth in one stand
Future workPost treatment mycorrhizal measurements
-Decrease in mycorrhiza tion
in response to fertilization
Use molecular methods to determine variation in mycorrhizal diversity across depth
Development of new AM primers may lead to a unified methodology for sampling mycorrhiza of both guilds
Acknowledgements
Ruth YanaiThomas Horton Tim Fahey
2010 Shoestring crewMatt VadeboncoeurApril DonerKikang Bae
MELNHE project and the Shoestring crewMcIntire-Stennis FundBartlettt experimental forest
Works cited• Brundett, M., N. Bougher, B. Dell, T. Grove, and N. Malajczuk. 1996. Working
with Mycorrhizas in Forestry and Agriculture. Australian Centre for
International Agricultural Research.
• Dickie, I. A., B. Xu, and R. T. Koide. 2002. Vertical niche differentiation of
ectomycorrhizal hyphae in soil as shown by T-RFLP analysis. New Phytologist
156:527–535. doi: 10.1046/j.1469-8137.2002.00535.x.
• Neville, J., J. . Tessier, I. Morrison, J. Scarratt, B. Canning, and J. . Klironomos.
2002. Soil depth distribution of ecto- and arbuscular mycorrhizal fungi
associated with Populus tremuloides within a 3-year-old boreal forest clear-
cut. Applied Soil Ecology 19:209–216. doi: 10.1016/S0929-1393(01)00193-7.
• Smith, S. E., and D. J. Read. 2008. Mycorrhizal Symbiosis, Third Edition, 3rd
edition. Academic Press.