Ergosterol as an Indicator of Endophyte Biomass in Grass Tissue
Endophytic fungi of cool-season grasses grow primarily in the intercellular spaces of the grass leaf sheath and the aleurone layer of infected seed (Hinton and Bacon, I 985). Because this association is completely endophytic, and therefore inaccessible, the growth and physiology of endophytes in planta is poorly understood. Microscopic analysis of sectioned and stained tissues remains the primary method for the identification and quantitation of hyphae in infected grass leaves (Bacon, 1992; Breen, 1992). Unfortunately, these methods are tedious and not suitable for routine work. Biochemical markers such as glucosamine, extracellular lacase and adenosine 5′- triphosphate have been used to quantitate fungal biomass in other complex materials (Matcham et al., 1985; Suberkropp et al., 1993), but these methods also have disadvantages such as poor reproducibility and the potential interference from compounds in the plant tissue itself.
KeywordsEndophytic Fungus Fungal Biomass Tall Fescue Aleurone Layer Infected Seed
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- Bacon, C. W. 1992. Isolation, culture, and maintenance of endophytic fungi of grasses. In Isolation of Biotechnological Organisms from Nature In D. R. Labeda, Ed.;McGraw- Hill: NewYork.Google Scholar
- Breen, J. R. 1992. Temperature and seasonal effects on expression of Acremonium endophyte-enhanced resistance to Schizaphis graminum ( Homoptera: Aphididae). Environ Entomo. 21: 68–74.Google Scholar
- Gessner, M. O., S. Y. Newell. 1997. Bulk quantitative methods for the examination of eukaryotic organoosmotrophs in plant litter. In Manual of Environmental Microbiology; C. J. Hurst; G. Knudsen; M. Mclnerey; L. Stetzen-Bach and M. Walter, Eds.; ASM Press: Washington,D.C.Google Scholar
- Matcham, S. E., B. R. Jordan, D. A. Wood. 1985. Estimation of fungal biomass in a solid substrate by three independent methods. Appl Microbiol Biotechnol. 21: 108–112.Google Scholar
- Seitz, L. M., H. E. Mohr, R. Burroughs, D. B. Sauer. 1977. Ergosterol as an indicator of fungal invasion in grains. Cereal Chem. 54: 1207–1217.Google Scholar