Plants, Pathogens and Algae: Modern Approaches to Fortify Global Food Security

Abstract

An increase in crop production will be necessary to offset the strain of population growth and climate change on the global food supply. One way to achieve this is to leverage bioengineering techniques in crops to enhance their process of carbon fixation – the conversion of atmospheric carbon dioxide (CO2) into biomass – thereby improving their yield efficiencies. Chlamydomonas reinhardtii is an algae that contains a sub-organelle structure, the pyrenoid, capable of uber-efficient carbon fixation. Essential to the pyrenoid’s functionality are structures known as tubules, which serve as intracellular CO2 conduits. Currently, little is known about how these tubules form. To identify proteins involved in pyrenoid tubulogenesis, I have i) created and executed bio-image analysis pipelines to analyze several mutant datasets, and ii) performed and optimized a modified co-immunoprecipitation assay in which I isolated and conducted proteomic analyses of intact thylakoid membrane fragments. In doing this, I have identified several promising tubulogenesis candidates, and improved a workflow capable of characterizing the complete pyrenoid tubule proteome. These results will advance our understanding of the pyrenoid and bring us closer to bioengineering the entire structure into land plants.

A second approach to increase global crop production is to minimize agricultural losses caused by plant disease epidemics. In order to intelligently transform agricultural practices to mitigate disease-driven yield losses, we need an acute understanding of how climate change will affect the epidemiological dynamics of plant pathogens. However, with the multitude of potentially additive and opposing effects of climate change on the biology and epidemiology of plant pathosystems, there is a seemingly endless number of outcomes that could occur. Here, I simulate simple stochastic SIR models of plant populations to explore what might reasonably occur under different climate change scenarios. My simulations suggest that climate change will cause population declines in the current geographic ranges of plants. Additionally, I show that plant population trajectories will depend highly on the identity of pathosystem parameters affected by climate change, and on the magnitude of perturbation. Ultimately, these results will help focus future research efforts, and inform our understanding of the nexus of climate change and plant pathosystems.