The five-year project funded by the United States Department of Energy will explore the genetic mechanisms of crassulacean acid metabolism (CAM), or ‘nocturnal photosynthesis’, a process exhibited by certain desert plants and first discovered at Newcastle University in the 1950s.
Unlike most plants which photosynthesize during the day, CAM plants take up carbon dioxide at night, allowing them to close their pores – or stomata – during the day and massively reduce water loss.
Taking in CO2 at night, the CAM plants build up a store of carbon which is used to power photosynthesis during the day. It is this property which enables CAM plants such as the prickly pear and agave to live in some of the world’s harshest environments.
UK lead Dr Anne Borland, a Reader in Molecular Plant Physiology at Newcastle University, said the aim was to further develop our understanding of these plants with a view to redesigning biofuel crops that could be grown on economically poor agricultural land.
“The long-term goal of the proposed research is to enhance plant adaptability to hotter, drier climates,” explains Dr Borland.
“CAM species such as agave and pineapple can grow and thrive with about 20-40 cm of precipitation a year, far less than the 50-100 cm per year required for current biofuel feedstocks.
“Ultimately, the aim is to introduce CAM-like properties into fast-growing species such as the poplar, enabling it to take up carbon dioxide at night and subsequently process this carbon during the day while the leaf pores remain closed.
“If successful, our research could lead to poplar that requires up to 80 percent less water for biomass production and consequently will be able to grow in more marginal habitats. In the longer term, the research has the potential to help tackle food security by maintaining the productivity of food crops in the drier and warmer world that climatologists predict for the next 60 years.”
The principal investigators on the US/UK project are US; John Cushman (Project Director)at the University of Nevada, Reno, US; Xiaohan Yang at Oak Ridge National Laboratory; Dr Borland, who holds a joint appointment in the School of Biology at Newcastle University and the Oak Ridge National Laboratory, Tennessee; and James Hartwell at the University of Liverpool, UK.
“With climate change predictions of 3.8 oC increase in temperature, a drop in reliable rainfall for many parts of the world and a greater need for sources of biofuels for transportation, these biodesign approaches to enhancing biomass production become very important,” Dr Cushman explained.
In order to identify the optimal ‘parts-list’ for introducing CAM-like properties into other plants, the team will undertake groundbreaking research on a diverse range of plants that use CAM, with the goal of identifying the key genes and proteins required to make this photosynthetic adaptation work efficiently.
They will be focusing on the poplar due to its fast-growing nature and wide-ranging habitat, which has led to it gaining worldwide recognition as a dedicated feedstock for biomass production. The tree also has a rich portfolio of genetic and genomics tools and resources.
The work is funded through the US-DOE’s Office of Biological and Environmental Research, Genomic Science: Biosystems Design to Enable Next-Generation Biofuels.
published on: 26th September 2012