© 2019 Photsynthessence  -  All photos by Adrienne Godschalx 

  • Instagram - White Circle
  • Twitter - White Circle
  • LinkedIn - White Circle

photosynthessence

   RESEARCH   

  HOW DO ECOLOGICAL SERVICES SHAPE PLANT CHEMISTRY?  

Plant biochemistry fundamentally influences all terrestrial ecosystems on our planet. Photosynthesis splits water in the light, forming energy-rich bonds from carbon dioxide. Carbon assimilation supports all food webs. Plants nourish a wide diversity of mammals, insects, fungi, and other primary consumers. In turn, plants are hardly defenseless.

 

Despite being rooted in place, plants have solved many ecological challenges biochemically. Plants produce an array of compounds to poison enemies, lure aggressive predators, direct pollen-carrying insects to plant sex organs, and negotiate peaceful trade agreements with microbes.

Virtually all plants rely on another organism to provide an ecological service. My research explores mechanisms by which symbionts select for particular chemical phenotypes, altering tritrophic food web pressure as well as influencing the stability of the symbiotic relationship.

 

Understanding symbiotic relationships brings us closer to developing sustainable solutions for pest management and grasping community-level food web dynamics through a functional approach to plant chemical ecology.

Despite being rooted in place, plants have solved many ecological challenges biochemically. Plants produce an array of compounds to poison enemies, lure aggressive predators for protection, navigate pollen-carrying insects to plant sex organs, and negotiate peaceful trade agreements with microbes. Virtually all plants rely on another organism to provide an ecological service. My research explores mechanisms by which plant-symbiont ecological interactions select for the evolution of a particular chemical phenotype.

Plant biochemistry fundamentally influences all terrestrial ecosystems on our planet. Photosynthesis splits water to form energy-rich carbon bonds that support all food webs. Plants nourish a wide diversity of mammals, insects, fungi, and other primary consumers. Yet, plant biochemistry also limits plant consumption, as secondary metabolites arm plants with toxic compounds, thick waxes, and chemical signals carrying information about the plant. Understanding plant chemistry brings us closer to developing sustainable solutions for pest management and grasping community-level food web dynamics through a functional approach to plant chemical ecology.

Plant families able to form a symbiosis with nitrogen-fixing bacteria, such as legumes with rhizobia, are relatively rare, but occur in most terrestrial ecosystems. Legume-rhizobia symbioses have been long-recognized to play critical roles in geochemical cycling and plant productivity, acclaimed as ecosystem engineers and keystone species. Gaining organic nitrogen (N) in exchange for photo-assimilated carbon (C) aids plants in overcoming soil nitrogen limitations, relevant both ecologically and agriculturally.  

 

How does symbiotic resource exchange influence food webs beyond plant productivity? How do rhizobia influence aboveground food webs from the bottom-up by mediating plant defense chemistry and tritrophic interactions?

NITROGEN- FIXATION

Plants can deploy volatile chemicals to advertise localized herbivore attack to other organisms that benefit from finding the same herbivores. Natural enemy recruitment, or indirect defenses, can effectively protect plant tissues from damage by attracting predators that kill or aggressively evict herbivores from the plant surface. Plants draw the attention of the third trophic level through specific VOCsand rewards such as sugar-rich extrafloral nectar (EFN).

INDIRECT DEFENSE

Tricking insects to mix genes for them requires  plants to hone in on attractive traits to trap their fly pollinators. What could be more attractive than steamy poop-mimicking floral volatiles? Are these plants attracting the most effective pollinators?

DECEPTIVE POLLINATION