You are here:
NATURAL ABUNDANCE STABLE ISOTOPE RATIOS SUPPORT MYCO-HETEROTROPHIC NATURE AND HOST -SPECIFICITY OF CERTAIN ACHLOROPHYLLUS PLANTS
Citation:
Trudell, S. A., P T. Rygiewicz, AND R. L. Edmonds. NATURAL ABUNDANCE STABLE ISOTOPE RATIOS SUPPORT MYCO-HETEROTROPHIC NATURE AND HOST -SPECIFICITY OF CERTAIN ACHLOROPHYLLUS PLANTS. Presented at 4th International Conference on Mycroohizas, Montreal, Quebec, Canada, August 10-15, 2003.
Description:
Over 400 species of achlorophyllous vascular plants are thought to obtain all carbon from symbiotic fungi. Consequently, they are termed ?myco-heterotrophic.' However, direct evidence of myco-heterotrophy in these plants is limited. During an investigation of the patterns of nitrogen and carbon stable isotopes of various ecosystem pools in two old-growth conifer forests, we sampled six species of achlorophyllous plants, considered to be myco-heterotrophic, to determine whether stable isotope ratios provide evidence of myco-heterotrophy and host-specificity within these symbioses. Dual-isotope signatures of the achlorophyllous plants differed significantly from those of all other pools. They were most similar to the signatures of ectomycorrhizal fungi, and least like those of green plants. a15N values of the achlorophyllous plants correlated strongly and positively with those of putative mycobionts. Used in conjunction with other methods, nitrogen and carbon stable isotope ratios can be used to demonstrate myco-heterotrophy and host specificity in these plants when other ecosystem pools are well characterized. This method also appears promising for estimating the degree of heterotrophy in photosynthetic, partially myco-heterotrophic plants.