Simple diagnostics for food security in developing countries

Central to the theme of the Agriculture and Food Systems Challenges (AFSC) is a need to maintain and improve the yield of crops. A recent FAO report highlighted that potatoes represent a very attractive proposition to address a number of the challenges which are pertinent to the AFSC. In particular:
1) 85 % of the plant is edible compared to 50 % for cereals
2) Potatoes are frugal users of water requiring less than half that of cereals.
3) Potatoes contain the highest protein content of any tuber or root crop and are a good source of Vitamin C.
4) Potatoes are much less affected by global commodity trading meaning that unlike cereals potato prices are generally much more related to local production costs.

Given these elements potato production is growing in the developing world, exceeding that of the developing world for the first time in 2005

In this project we aim to develop our novel potato disease detection system to address 2 of the major issues found in the potato supply chain:
1) Viral infection – A cause of crop yield reduction (e.g. reported in Pakistan to reduce yield by up to 83%)
2) Pectilytic bacteria - A cause of post-harvest potato loss

THE TECHNICAL SOLUTION
Over the past 8 years we have developed a new method for biodetection that substantially simplifies the equipment required to make quantitative measurements of target analytes. The method uses the combination of novel reagent and a simple optical detection system. The reagent is based on a protein nanofibre dereviatised with disease recognition elements (e.g. antibodies, aptamers, DNA). The detection system uses simple handheld solid state optical system to detect changes in the absorbance of polarised light to produce a linear dichroism signal (LD) (see https://tinyurl.com/l7sz58o for an explanation). Together these elements provide an assay that is fast, robust and reliable, making it ideally suited to agricultural testing.

This work has culminated with the establishment of a UoB spin out company Linear Diagnostics Ltd (LDL). As part of a IUK project (with LDL) we produced a commercial test for pectolytic bacteria e.g. Dickeya dianthicola. We then received EPSRC GCRF funding to develop a second test for viral potato diseases for the developing world.

This funding has catalysed:
1) Development of a new DNA-based testing system with market leading sensitivity making the technology applicable to a much wider range of plant pathogens.
2) Development of the world’s first remote and rapid DNA test for viral potato pathogens (the most important pathogen in sub-Saharan Africa)
3) Establishment of co- funded collaboration with Science Advice for Scottish Agriculture (SASA), one of three leading laboratories carrying out potato pathogen surveillance globally. The project will develop bench testing methods at SASAS for real world validation of our tests.
4) Visits to Prof. Dirk Bellstedt at the University of Stellenbosch, SA, the world leader in potato pathogen research and provision in Africa. Prof. Bellstedt has offered to advise and support us with understanding the specific challenges of implementing these tests in sub-Saharan Africa

This studentship application aims to capitalise on this significant progress working to develop both reagents and hardware for use in pathogen detection by potato growers in sub-Saharan Africa. It is also expected that during the studentship TD/JT and our collaborators will develop a case for external GCRF funding.

The project involves expertise in 2 key areas:
1) Development of assay reagents. This involves production of viral nanoparticles and derivatisation of their surface with DNA/Antibodies. From previous experience with graduate and UG students these skills are easily learnt by candidates with either biochemistry or chemistry as their background.
2) Development of instrumentation. TD’s laboratory already carries out instrument development for a number of projects. It will be important that a candidate would be happy to engage in this activity and ideally some engineering background would be helpful.
Hence An ideal candidate for the project would be someone with chemical/biochemical engineering background, although we do not preclude candidates skilled in biochemistry or chemistry. We would also be looking for a candidate with interests in addressing global challenges and who is willing to help us develop the collaborations for the success of the project.