Create your own conference schedule! Click here for full instructions

Abstract Detail



Paleobotany

Gulbranson, Erik L [1], Harper, Carla J [2].

Isotopic characterization of plant-fungus interactions in modern and fossil woods.

Morphological studies of fossil wood rotting and pathogenic fungi are in the relatively early stages as a research foci, however, in depth studies on the geochemical pathways of degradation and decay symptoms in fossils remain even less understood. The relative abundance or relationship of certain pathogenic microorganisms with specific fossil taxa is an underutilized parameter of paleoecological analyses. This is perhaps due in part by the current lack of screening tools to supplement optical microscopic methods of investigation. The study presented herein incorporates stable carbon isotope analyses of various forms of plant-fungus decay features in modern wood spanning several genera of gymnosperms and angiosperms. Preliminary results suggest that fungal decay signs and symptoms in white pocket rot infected trees and host responses, i.e., Compartmentalization Of Decay In Trees (CODIT) response, reveal characteristic isotopic patterns. We provide documentation of specific sampling strategies to characterize the compositional changes to wood during saprotrophic interactions and potential host responses. The geochemical pathways of degradation are interpreted based upon comparison of stable isotope patterns in identical sampling strategies for control samples and the expected trend of decay products from preferential microbial-metabolism of lignin. The isotopic results from extant plants are compared to fossil woods that display morphologic evidence of fungal decay structures; fossil woods underwent identical sampling strategies as the modern woods. The similarity of isotopic patterns between fossil and extant fungal decay structures indicates that geochemical pathways of wood decay in the modern are of great antiquity. Moreover, these interpretations of metabolic process are supported by characterization of fossil wood organic compounds, illustrating the potential to detect host responses as well as elucidating specific changes in wood geochemical composition from fungal decay versus thermal diagenesis. Geochemical techniques such as stable carbon isotope analysis can be used to broadly screen fossil woods for the presence of saprotrophic or pathogenic relationships in deep time, which can be further studied in depth via morphologic analysis, organic geochemistry, and high-resolution mass spectroscopy techniques.


Log in to add this item to your schedule

1 - University of Wisconsin-Milwaukee, Geosciences, 3209 N. Maryland Ave, Milwaukee, WI, 53211, USA
2 - University Of Kansas, Ecology And Evolutionary Biology, 2041 Haworth Hall, 1200 Sunnyside Avenue, Lawrence, KS, 66045, USA

Keywords:
isotopes
fossil fungi
wood decay
Permian
Triassic
Antarctica.

Presentation Type: Oral Paper
Session: 17, Paleozoic and Mesozoic paleobotany
Location: Sundance 3/Omni Hotel
Date: Tuesday, June 27th, 2017
Time: 8:45 AM
Number: 17004
Abstract ID:246
Candidate for Awards:None


Copyright © 2000-2017, Botanical Society of America. All rights reserved