1. Colonized Root
(100X)
Root Lacking Colonization
(100X)
INVESTIGATION OF SALTMARSH PLANTS FOR THE PRESENCE OF MYCORRHIZAL FUNGI
1 Mississippi Gulf Coast Community College-Jackson County Campus, Gautier, MS
2 University of Southern Mississippi, Gulf Coast Research Laboratory, Ocean Springs, MS
LITERATURE CITED
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Allen MF. 1992. Mycorrhizal functioning: An integrative plant-fungal process. Chapman and Hall, New York
Boullard B. 1985. Les mycorrhizae des especes de contact marin et de contact salin. Revue de Mycologie. 23: 282–317.
Burke DJ, Hamerlynck EP and Hahn D. 2002. Interactions among plant species and microorganisms in salt marsh sediments. Applied and
Environmental Microbiology 68: 1157–1164.
Dehne HW. 1982. Interaction between vesicular-arbuscular mycorrhizal fungi and plant pathogens. Phytopathology 72: 1115–119.
Harley JL and Smith SE. 1983. Mycorrhizae Symbiosis. Academic Press, London.
Hoefnagels MH, Broome SW, and Shafer SR. 1993. Vesicular-arbuscular mycorrhizae in salt marshes in North Carolina. Estuaries 16: 851-858.
INVAM. 2007. http://invam.caf.wvu.edu
Kandalepas D, Platt W, 2006.Fungi may help in re-establishment of marsh plants after hurricanes. Ecological Society of America Annual Meeting,
Memphis, Tennessee.
Khan AG, 1974. The occurrence of mycorrhizas in halophytes, hydrophytes, and xerophytes, of Endogone spores in adjacent soils. Journal of General
Microbiology 81:7-14.
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and Principles of Mycorrhizal Research. American Phytopathological Society. pp 69-76
Mercer L.P. 1984. A biological and fisheries profile of the spotted seatrout, Cynosion nebulosus. North Carolina Department of Natural Resources and
Community Development, Division Marine Fish. North Carolina Special Scientific Report 40, Morehead City.87p.
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Proceedings of the National Academy of Sciences 77: 2113–2118.
Mason E. 1928. Note on the presence of mycorrhizae in the roots of salt marsh plants. New Phytologist 27: 193–195.
Mitch WJ and Gosselink JG. 2000. Wetlands, 3rd Edition, Van Nostrand Reinhold. New York. pp 639–644.
Rozema J, Arp W, van Diggelen J, van Esbroek M, Broekman R and Punte H. 1986. Occurrence and ecological significance of vesicular arbuscular
mycorrhiza in the salt marsh environment. Acta Botanica Neerlandica 35: 457–467.
Sengupta A and Chaudhuri S. 1990. Vesicular arbuscular mycorrhiza (VAM) in pioneer salt marsh plants of the Ganges river delta in West Bengal
(India). Plant and Soil 122: 111–113.
Sylvia DM. 1990. Distribution, structure and function of external hyphae of vesicular-arbuscular mycorrhizal fungi, in Rhizosphere Dynamics. Box JE
and Hammond LC. Eds. Westview Press, Boulder, CO. pp.144–167.
Tobar RM, Azcon R, Barea JM. 1994. Improved nitrogen uptake and transport from 15 N-labeled nitrate by external hyphae of arbuscular mycorrhiza
under water-stressed conditions. New Phytologist 126: 119–122.
Vierheilig H, Coughlan AP, Wyss U and Piche Y. 1998. Ink and vinegar, a simple staining technique for arbuscular-mycorrhizal fungi. Applied and
Environmental Microbiology 64: 5004–5007.
Wigand C and Stevenson JC. 1994. The presence and possible ecological significance of mycorrhizae of the submerged macrophyte, Vallisneria
americana. Estuaries 17: 206–215.
ACKNOWLEDGMENTS
The authors would like to thank Dr. L. Melton (MGCCC) and Dr. S. Brown (USM) for assistance with coordinating this project and Diana
Reid (GCRL) for poster printing assistance.
RESULTS AND DISCUSSION
The roots of the plants collected from the marsh behind GCRL were all found to be colonized with AMF, whereas plants collected from other locations were not colonized.
One of the benefits of AMF is an increase in nutrient uptake. In infertile soils, nutrients taken up by the mycorrhizal fungi can lead to improved plant growth and reproduction. The results of this study suggest
that the areas of marsh behind GCRL may be low in nutrients as all plants were colonized with AMF, whereas the areas along the shoreline may be higher in nutrients as none of these plants were colonized
with AMF. Further studies, including analysis of the sediment, are required to confirm this.
ABSTRACT
Coastal saltmarshes provide protection from erosion and hurricane damage, and offer nursery habitats for
ecologically and commercially important marine species. However, the total acreage of saltmarsh is in rapid
decline worldwide. This poses many problems, commercially and environmentally. Continued loss of saltmarsh
habitats could lead to a dwindling number of important commercial fisheries, as well as many other forms of
marine life. The number of saltmarsh restoration projects is on the rise, but the success rate of these projects is
only around fifty percent. Therefore, new methods are being developed to increase the health of plants grown in
nurseries, such as the root colonization of emergent vegetation by symbiotic mycorrhizal fungi. The colonization
of saltmarsh plants by certain species of mycorrhizal fungi could lead to improved nutrient uptake and therefore
better health of saltmarsh plants in the nursery. Samples of native marsh sediment and roots from the dominant
emergent vegetation species of the Gulf Coast, Spartina alterniflora, were collected and investigated for the
presence of these fungi. The amount of naturally occurring mycorrhizal fungi found at different coastal saltmarsh
sites was then compared.
INTRODUCTION
Saltmarsh communities are a common sight along the intertidal zone of Louisiana and Mississippi
coastlines. Saltmarshes are important vegetated habitats that are preferentially utilized by a multitude of species
as juvenile nursery areas, and therefore these areas are classified as essential fish habitat. Saltmarshes however
are declining, with 73% of the nation's estuaries moderately or severely degraded between 1940 and 1983 alone
(Mercer 1984). This is primarily due to human activities on land, boating, land reclamation and other construction
in the coastal zone, dredge-and-fill activities and destructive fisheries practices (Mitch and Gosselink 2000). The
loss of these valuable habitats gives urgency to protect, conserve and restore these important resources. In
efforts to overcome the loss of these valuable habitats, salt marsh restoration projects are on the increase. We
plan to investigate the role of symbiotic root association in fungi. These symbiotic fungi form associations with
roots of plants and are known as arbuscular mycorrhizal fungi (AMF). Nutrients taken up by AMF can lead to
improved plant growth and reproduction (Harley and Smith 1983, Allen 1992). Generally, with AMF associations
there is a benefit to both plant and fungi: the fungi obtain photosynthate from the host plant and the plant benefits
from added surface area for nutrient uptake (Hoefnagels et al 1993). Additionally, AMF may improve resistance to
pathogens, and enhance plant survival in stressful environments including: transplant shock (Dehne 1982,
Linderman and Hendrix 1982), water-stress (Tobar et al. 1994), salinity stress (Allen and Cunningham 1983), and
low nutrient availability (Wigand and Stevenson 1994). As such, plants with AMF are often more competitive and
better able to survive (Sylvia 1990). AMF occur in nearly 80% of terrestrial plant communities (Read et al 1976,
Malloch et al 1980, Harley and Smith 1983), but have rarely been studied in saltmarsh plants (Wigand and
Stevenson 1994). AMF were presumed absent from waterlogged or submersed habitats (Harley and Smith
1983), but they have been found in saltmarsh plants in several countries including Pakistan (Khan 1974), India
(Sengupta and Chaudhri 1990), France (Boullard 1985), Great Britain (Mason 1928) and the Netherlands
(Rozema et al. 1986). They are thought to assist plants during times of psychological stress (Hoefnagels et al
1993, Burke et al 2002). Kandalepas and Platt (2006) found that the majority of saltmarsh plants that perished
during Hurricane Katrina were not infected with AMF prior to the storm, whereas those that survived the hurricane
showed signs of AMF infection both before and after the storm, suggesting that AMF associations can survive
hurricanes and may play a critical role in saltmarsh plant survival. The interaction between AMF and saltmarsh
plants is an understudied area that has many implications for future restoration efforts.
MATERIALS AND METHODS
The entire plant and roots of Spartina alterniflora were collected from various locations in Davis Bayou in the
Mississippi Sound, including along the shoreline of East Beach, as well as from the marsh behind the Gulf Coast
Research Laboratory. The plants were returned to the lab and stored in the dark at 4C. Root samples were then
cleaned, cut and stained in ink and vinegar following the procedures of Vierheilig et al (1998). Using this method,
the chitin in fungal cell walls stains blue-black, while plant material remains hyaline/reddish-brown. Root samples
were examined using light microscopy to detect the presence of fungi.
Cutting roots from Spartina alterniflora plantsCollecting Spartina alterniflora plants
Saltmarsh Collection Sites
Staining procedure
Collected Spartina alterniflora plant
ready for cutting
Staining procedure
Beach 2 site
Making collections behind the Caylor building at the
Gulf Coast Research Laboratory, Ocean Springs, MS
Table 1 Collecting Locations
Caylor 1 site
Aimie Chambliss1, Melissa Adriano2, Allison K. Walker2 and Jinx Campbell2
Root Staining Procedure
Gulf Coast Research Laboratory
Caylor 7 site
Pier site
Date Location Mycorrhizal Status (+/-)
10/23/2008 East Beach Negative
10/23/2008 Caylor Marsh Positive
11/6/2008 East Beach Negative
11/6/2008 Pier Negative
11/6/2008 Caylor Marsh Positive
1/27/2009 Caylor Marsh Positive