Study source-sink and transport attenuation of photosynthesis

PhD-level assistantship and post-doctoral scholar position available in the Tree Ecophysiology Lab

Photosynthesis is limited by the capacity of plants to translocate sugars from leaves to sinks. Source-sink relations affect translocation and thus may be key in optimizing photosynthesis in crop plants broadly. The selected candidates will be working on a USDA AFRI-NIFA Foundational project to quantify the interacting relationships among source-sink allocation, carbohydrate translocation speeds, and the regulation of net carbon fixation. The underlying hypothesis of this work is that increased allocation to sink growth interacts with phloem transport limitations to govern the regulation of carbon fixation. Thus, carbohydrate allocation can be co-optimized to enhance net assimilation rates. 

The selected candidates will be involved in a variety experiments to quantify these underlying relationships and the degree to which they affect growth. Experiments will include the impact of ploidy on translocation characteristics, methods of assessing total sink demand, impact of loading on translocation speed, and population-wide growth analysis and photosynthetic regulation. The selected candidate will have the opportunity to use unique methodologies at the UF Tree Ecophysiology Lab, including a range of methods to assess photosynthesis and radioisotopic methods of assessing carbohydrate translocation and allocation, as well as collaborate in assessing genetic components regulating these process. This project will focus on the woody subtropical genus, Citrus, but opportunities to collaborate across disciplines or species groups will be sought and encouraged. The work involves combinations of field, greenhouse, and laboratory work.

The work environment is highly collaborative, and demonstration of the ability to work in diverse teams will be valued in the selection process. Critical thinking, independent judgment, and interest in the subject matter are essential. Other valued skills include: 

  • Quantitative analysis 
  • Written communication in an academic setting
  • Experience with gas exchange methods
  • Knowledge of plant carbohydrate allocation processes or phloem function

The ecophysiology lab (website here) at the Citrus Research and Education Center in Lake Alfred, Florida, uses whole-plant physiological approaches to address challenges in horticultural productivity in perennial plants. The Citrus Research and Education Center offers ample opportunities for collaboration with 25 labs working in areas as varied as genetics, plant pathology, and entomology. The PI of the Tree Ecophysiology lab places a high importance on mentorship and the development of skills of and opportunities for students and post-doctoral scholars. If interested please send inquiries or a resume to Christopher Vincent at civince@ufl.edu.