Research in the lab broadly addresses questions on species interactions and adaptation. We also continue longstanding interests to understand plant growth, defense, and other functional traits as they change under biotic and abiotic stress, especially with regard to plant parasitism. All paths meet as we try to understand how these interactions evolved, persist, or can be managed.
Plant response to its environment
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Plant signaling pathways are highly interconnected and can result in tradeoffs or shared networks that underlie the final phenotype. Induced phenotypes occur when other organisms modify plant physiology or morphology, often to the benefit of the attacker. We combine field and lab research on plant ecology and physiology with modern laboratory methods in genomics to identify the genetic basis for how plants respond to their environment, and what initiates phenotypic change. Often we employ a systems biology approach, e.g., using genomics, transcriptomics, and proteomics, to identify candidate processes for further study. Broadly, our goals are to:
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Some arthropods dramatically alter their plant host as they co-opt multiple signaling and development pathways to generate neoplasms, called galls, or manipulate immunity to avoid detection. Very little information exists to explain how and what processes or effectors galling species use to usurp plant development.
Some plants evolved to use other plants as resources including water, nitrogen, heterotrophic sources of carbon, and ecologically important secondary metabolites, often because their environment is limited in some resource. How and what resources limit co-infections or hemiparasitic species interactions with hosts remain enigmatic.
Currently we are using several systems to investigate how plant signaling networks and resource dynamics relate to biotic perturbations of various context, including agricultural management systems, presence/absence of microbiota, varying levels of resistance genes, and species interactions.
Recent work: Rafterty et al 2019 lays some groundwork on the context that determines plant parasitism, and Nabity et al 2021 follows up on this by examining how competition alters resource availability.
Recent work: Rafterty et al 2019 lays some groundwork on the context that determines plant parasitism, and Nabity et al 2021 follows up on this by examining how competition alters resource availability.
Evolution and function of herbivore effectors
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One exciting path is to investigate how insects co-opt plant growth and development by characterizing insect effectors and their plant targets. For this research we are annotating several insect genomes to identify and validate predicted effectors and their plant targets. We are using the phylloxerids as one model assemblage because of their unique trait diversity, host breadth and economic importance.
We also are examining host breadth and resistance to the wooly apple aphid, Eriosoma lanigerum, as we seek to understand its complex life cycle, novel manipulation of plant hosts tissues, and resistance to cultivated apple genotypes. We have collaborations to work on cowpea-aphid and brassica-fly interactions using a similar approach. |
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Recent work: Zhao et al 2019 introduces use to candidate effectors that alter proteasomal function. Rispe et al 2020 showcases the breadth of herbivore genes that enable plant feeding. Our collaborative genome projects continue to add more context on what it takes to become an herbivore.
Current Collaborations with data in prep
With the genome now complete for Scaptomyza flava, we are pursuing our findings about what effectors this insect has and how they interact with plants.
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Sometimes we take breaks from research to enjoy our field sites.
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Field work across Arizona: Sycamore Canyon, Clear Creek, Santa Rita Experimental Range
