Projects

Research Projects

The following summaries provide an introduction to our current projects; for more detailed information, please visit the pages.

Phosphate: essential for food security and sustainable agriculture

Phosphate is essential for agriculture, but is a limiting, non-renewable resource.  Much of the phosphate currently applied to crops as fertiliser is wasted and pollutes the environment before plants can absorb it.  To promote food security and sustainable agriculture, it is paramount to better understand the mechanisms that control growth behavior in response to low phosphate and to increase the efficiency with which crops assimilate and use phosphate.  One important strategy of plants to increase their capacity to acquire phosphate is to alter the growth patterns of their root systems in low phosphate: We want to understand how this happens, so we can manipulate it to make root systems more efficient in nutrient uptake.  We have started to identify key processes in root growth control in low phosphate that affect the activity of the root apical meristem, and are now aiming to further study these while also initiating transfer of this knowledge to crops.

Wild-type Arabidopsis plants growing on media with adequate phosphate or lacking sufficient phosphate, respectively. The media is also low (but sufficient) in iron content to avoid the artifactual iron-dependent root growth inhibition observed in low phosphate when iron is supplied in excess. Growth attenuation can be seen in the decreasing growth intervals (marked by the white lines) close to the root tips on the right.

Root System Architecture: enhancing resource use and climate resilience for sustainability

Root system architecture (RSA) describes the three-dimensional distribution of roots in the soil and the changes over time. While the root system of each individual in different soils varies, plants of a species or variety display characteristic distributions and their RSA is very similar when growing in the same conditions. RSA of a crop has a huge impact on its ability to acquire resources and to withstand stresses such as drought. We have developed frugal, commodity-based resources to characterise RSA in soil-grown plants: using image capture, in combination with machine learning, our lab and collaborators at the School of Engineering have developed a system based on commodity components that allows colleagues and citizen scientists in low- and middle-income countries to evaluate below-ground crop performance aimed at enhancing yields. We are now interested to also utilise this system in the UK to enhance the climate resilience of barley.

Chickpea root systems at different timepoints after sowing and their growth dynamics (from Bontpart et al. (2020): Affordable and robust phenotyping framework to analyse root system architecture of soil-grown plants. The Plant Journal. 103 2330; doi: http://dx.doi.org/10.1111/tpj.14877

Stem cells and cell differentiation in plants

The meristems at the growing tips of roots and shoots contain stem cells and their immediate progeny, so-called transit amplifying cells.  The progression from stem cells to differentiated cells that transient amplifying cells undertake is a gradual process: involving an initial phase of rapid cell divisions followed by the extinction of proliferation at the meristem boundary.  Nonetheless, a modified cell cycle persists in these post-mitotic cells, manifested by several rounds of genome duplication (endoreplicating cells) that proceed concomitantly with cellular differentiation. Mitotic exit is of great importance for plant growth control: in plants that experience environmental stress, cells prematurely lose the capacity to divide, thereby reducing growth capacity, and hence, recovery following a stress episode.  Likewise, such differentiated plant cells in general lack the capacity to resume proliferation, and therefore cells that express the metabolic networks for the production of high value chemicals (bio-active compounds cannot be cultivated.  This is because most cultured plant cells lose their differentiation state (which is critical for their ability to produce bio-active compounds) rapidly.  We are interested to identify the mechanisms by which the differentiated state is reversed (reprogrammed) in regenerating plants and what the impediments are to proliferation in differentiated cells.  We have developed new tools to isolate and enrich plant protoplasts, and are studying the mechanisms of de-differentiation with the aim to use plant cells in the future as the basis for a new biotechnological industry.