ARS | Publication request: IMPLICATIONS OF PLANT-FUNGAL INTERACTIONS: CAN MICROSCALE PROCESSES HAVE MACROSCALE IMPACTS?

Submitted to: Chihuahuan Desert Symposium
Publication Type: Abstract Only
Publication Acceptance Date: October 1, 2004
Publication Date: October 15, 2004
Citation: Lucero, M.E., Barrow, J.R. 2004. Implications of plant-fungal interactions: can microscale processes have macroscale impacts [abstract]? Sixth Symposium on the Natural Resources of the Chihuahuan Desert Region, October 14-17, 2004, Alpine, Texas. p. 32.

Technical Abstract: The roles microorganisms play in shaping desert plant communities have often been underestimated. Recent tools expanding our abilities to detect, identify, and monitor microbial inhabitants of plant tissues are providing new insights to amazingly complex systems. Microscale examination of Bouteloua eriopoda (black grama grass) and Atriplex canescens (four-wing saltbush) has revealed diverse fungal communities living within individual plants. The compositions of these fungal communities are apparently dictated by multiple factors. We believe these internal fungi assist the plant with water and nutrient transport, drought tolerance, and defense against herbivores and pathogens. To explore thresholds of plant fitness that are defined by microbial communities, we transferred fungi inhabiting Bouteloua eriopoda, Atriplex canescens, and Sporobolus cryptandrus to eight, nonhost plant species. Dramatic, whole-plant differences in morphology, water potential, chlorophyll content, dates to maturity, seed production and marker gene profiles, and more between treated and untreated plants, were observed. In most cases, endophyte transfer at the cellular level produced astonishingly robust plants with greater reproductive potential than the untransformed counterparts. The dramatic changes observed in plants with altered microbial populations illustrate the propagation of cellular-level changes to whole-plant and progeny-scale impacts. We hypothesize that these transformed plants will continue to grow, reproduce, and disperse more rapidly than their native counterparts, propagating changes from the plant-microbe interface to ecologically significant scales. Broad-scale factors limiting this process are being explored.