Ectomycorrhizae Endomycorrhizae

Arbuscular mycorrhizae
Ectomycorrhizae
Endomycorrhizae
Ericoid mycorrhizae
Orchid
mycorrhizae
Ectendomycorrhizae
http://www.microbiologyprocedure.com/mycorrhizae/ectomycorrhizae.html
Ectomycorrhizae (ECM)
• “Ecto-” means outside and in the case of ECM it
means the fungal hyphae do not normally penetrate
into healthy cortical cells of the plant
• Mantle (m): fungal sheath on the root surface like a
glove
• Hartig net (n): hyphae between root epidermal and
cortical cells (c)
Mantle
Hartig net
Primary phloem
Primary xylem
Endodermis
Cortical cell
Hypha
(non-mycorrhizal “textbook” root c.s.)
Ectomycorrhizae
are morphologically distinctive
Ectomycorrhizae
© Kwantlen.ca/Horticulture
http://cropsoil.psu.edu/sylvia/morpho
Most ECM fungi are
Basidiomycota
(e.g. Amanita, Amanita,
Boletus, Cantharellus,
Cortinarius, Entoloma,
Entoloma, Gomphidius,
Hebeloma, Hygrophorus,
Inocybe, Lactarius, Paxillus,
Rhizopogon, Russula,
Scleroderma, Scleroderma,
Suillus, Thelephora,
Tomentella)
Ectomycorrhizae
Peterson, R.L., et. al. 2006 ,
Kwantlen.ca/Horticulture
Some ECM fungi
are Ascomycota
(e.g. Cenococcum,
Muciturbo,
Sphaerosporella,
and, as shown,
Tuber)
Peterson, R.L., et. al. 2006
And a few ECM fungi are Zygomycota
(in the genus Endogone and Glomus)
Ectomycorrhizae
© Kwantlen.ca/Horticulture
ECM predominantly occur on the roots of tree species in the
Pinaceae (ECM only), Fagaceae, Betulaceae, Salicaceae (may
also form AM, a type of endomycorrhizae).
• Hyphae emanating from the mantle may extend
several centimeters in to the surrounding soil
• Hyphae are small diameter and long and therefore
have a much greater surface area than do roots or
root hairs
• Hyphae access soil micropore space to reach more
water and nutrients in dry conditions
• Hyphae may also maintain hydraulic conductivity
with the soil as it dries and shrinks
Ectomycorrhizae
© Kwantlen.ca/Horticulture
Root hair
Hypha of Cenococcum geophyllum
>2000 hyphae
may emanate
from one
mycorrhiza
4 m of hyphae
in 1 mL of soil
Peterson, R.L., et. al. 2006
Ectomycorrhizae
Trappe and
Vogel, 1977
© Kwantlen.ca/Horticulture

Hyphae may combine to from mycelial strands or
rhizomorphs

May grow several meters and transport water and nutrients
(especially Nitrogen, Phosphorus, Potassium) to the roots
Ectomycorrhizae
© Kwantlen.ca/Horticulture
ECM may protect against root pathogens
• Species of certain ECM fungi (e.g. Lactarius,
Cortinarius, and Hygrophorus) produce antibiotic
substances
• Some of these antibiotics are antifungal on
Rhizoctonia solani, Pythium debaryanum and
Fusarium oxyporum
• The mantle may exclude nematodes
http://www.microbiologyprocedure.com/mycorrhizae/resistance-to-plant-diseases-by-ectomycorrhiza.html
Ectomycorrhizae
© Kwantlen.ca/Horticulture
Pratylenchus
penetrans
Peterson, R.L., et. al. 2006
http://plpnemweb.ucdavis.edu
Abiotic Disorders & ECM



Nutrient deficiency symptoms less likely on
ECM plants
Leaf scorch symptoms less likely as many
ECM fungi can grow at water potentials well
below the permanent wilting point of the plant
Toxic metals (Fe, Al, Mn, S) or excessive
nutrients are more likely filtered out on ECM
plants
Smith, S.E. and. D.J. Read. 1997
Ectomycorrhizae
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Photo Credits (images with no URL shown)
Peterson, R.L., et. al. 2006. Mycorrhizas: Anatomy and
Cell Biology Images. NRC Research Press.
Roth, A.L. 1990. Mycorrhizae of Outplanted Conifers.
M.Sc. Thesis. University of British Columbia. 298 p
Roth, A.L. Kwantlen Plant Database
(www.Kwantlen.ca/Hort)
Ectomycorrhizae
© Kwantlen.ca/Horticulture
Selected References
Smith, S.E. and. D.J. Read. 1997. Mycorrhizal Symbiosis
(2nd Ed.). 605 pp. Academic Press, San Diego and
London
Whipps, J.M. 2000. Microbial Interactions in the
Rhizosphere. J. Exp. Botany. V. 52: 487-511
Zhang, R.Q. et. al. 2010. Forest Pathology (on-line) 28 JUL
2010
Ectomycorrhizae
© Kwantlen.ca/Horticulture