Exploiting variation in the regulation of carbon assimilation to improve wheat productivity

Current rates of yield increase for major food crops are insufficient to meet the projected doubling of food demand by 2050. Higher yielding and climate resilient crops must be developed to mitigate the negative impacts of climate change and ensure future food security. Photosynthetic CO2 assimilation is the main determinant of plant biomass production, and it is an inefficient biological process with capacity for substantial improvement. This project focuses on improving the regulation of the CO2-fixing enzyme, Rubisco, with the goal of increasing the efficiency and climate resilience of carbon assimilation and biomass production in wheat.

Regulation of Rubisco activity by its molecular chaperone, Rubisco activase (Rca), directly impacts on the response of carbon assimilation to environmental stimuli, in particular fluctuating light and warm temperatures. This regulatory mechanism is not optimal to sustain carbon assimilation and crop biomass production in current and projected, warmer and more variable, climates. This is partly because the activity of Rca is extremely sensitive to elevated temperatures and limits photosynthesis under moderate heat stress. Experimental results obtained with the model plant species Arabidopsis suggest that there is variation in the light response and thermal tolerance of Rca, and that this variation can be exploited to improve carbon assimilation. Diversity in the properties of Rca enzymes available in nature needs to be better understood if we are to exploit this strategy in crops.

This PhD project will test the hypothesis that variation in Rca genes and protein isoforms exists and can be exploited to drive substantial improvement of wheat biomass and grain yields. Firstly, we will determine variation in Rca genes and isoforms occurring in wheat and wheat relatives adapted to diverse environments. The student will then characterise the biochemical properties, namely the light and temperature response, of the diverse Rca isoforms identified. Subsequently, the student will compare Rubisco activity, photosynthesis and plant biomass production in plants containing diverse Rca isoforms to (a) establish an association between the ability of Rca to maintain Rubisco activity and wheat biomass production, and (b) identify Rca isoforms that will substantially increase genetic wheat yield potential.

Further Information: http://www.lancaster.ac.uk/sci-tech/downloads/phd_251.pdf

Academic Requirements: First-class or 2.1 (Hons) degree, or Masters degree (or equivalent) in an appropriate subject.

Deadline for applications: 14 February 2016

Provisional Interview Date: [tbc] Week Beginning 29 February 2016

Start Date: October 2016

Application process: Please upload a completed application form (download from http://www.lancaster.ac.uk/media/lancaster-university/content-assets/documents/lec/pg/LEC_Funded_PhD_Application_Form.docx) outlining your background and suitability for this project and a CV at LEC Postgraduate Research Applications, http://www.lec.lancs.ac.uk/postgraduate/pgresearch/apply-online.

You also require two references, please send the reference form (download from http://www.lancaster.ac.uk/media/lancaster-university/content-assets/documents/lec/pg/LEC_Funded_PhD_Reference_Form.docx) to your two referees and ask them to email it to Andy Harrod ([Email Address Removed]), Postgraduate Research (PGR) Co-ordinator, Lancaster Environment Centre by the deadline.

Due to the limited time between the closing date and the interview date, it is essential that you ensure references are submitted by the closing date or as soon as possible.