4 South 1.11
Tel: +44 (0) 1225 383572
Dr John Beeching
Cassava (Manihot esculenta) is the world’s sixth most important crop in terms of production and is the staple food of over 700 million in the tropical regions of the world, being of particular importance in sub-Saharan Africa. With increasing population pressures and demand for food in these regions the production of cassava will need to increase over the next few decades; as a result cassava is now an international priority crop for improvement.
The starchy storage roots of cassava deteriorate rapidly upon harvesting rendering them unpalatable and unmarketable with 24 – 72 hours. With increased urbanisation and the entry of cassava into the cash economy this post-harvest deterioration physiological (PPD) has become a major constraint to the development and exploitation of this crop impacting on producers, processors and consumers alike. Extending the shelf-life of cassava roots to one to two weeks would resolve this bottleneck, unlocking the crop's full potential and converting cassava into a modern crop for Africa and the world.
The prime focus of my laboratory is directed towards understanding and ultimately controlling this deterioration process. PPD is an active process involving changes in gene expression, the synthesis of novel proteins and changing profiles of accumulation of secondary metabolites. Work using cDNA micro-arrays has confirmed the central role of reactive oxygen species (ROS) and has led to a model of PPD as a ROS-mediated programmed cell death (PCD). We are testing candidate genes in transgenic cassava for their ability to modify the anti-oxidant and anti-PCD status of the storage roots. Potentially these constructs may have the ability to delay the deterioration response.
This research forms part of major collaborative projects with national and international laboratories in Africa, Europe, Latin America and the US aimed at addressing the major constraints to the improvement of cassava as a crop.
Xu, J., Duan, X., Yang, J., Beeching, J.R. and Zhang, P., 2013. Coupled expression of Cu/Zn-superoxide dismutase and catalase in cassava improves tolerance against cold and drought stresses. Plant Signaling and Behavior, 8 (6), e24525.
Xu, J., Duan, X., Yang, J., Beeching, J.R. and Zhang, P., 2013. Enhanced reactive oxygen species scavenging by overproduction of superoxide dismutase and catalase delays postharvest physiological deterioration of cassava storage roots. Plant Physiology, 161 (3), pp. 1517-1528.
Gbadegesin, M. A. and Beeching, J. R., 2011. Isolation and partial characterization of a root-specific promoter for stacking multiple traits into cassava (Manihot esculenta CRANTZ). Genetics and Molecular Research, 10 (2), pp. 1032-1041.
Sayre, R., Beeching, J. R., Cahoon, E. B., Egesi, C., Fauquet, C., Fellman, J., Fregene, M., Gruissem, W., Mallowa, S., Manary, M., Maziya-Dixon, B., Mbanaso, A., Schachtman, D. P., Siritunga, D., Taylor, N., Vanderschuren, H. and Zhang, P., 2011. The BioCassava Plus Program: biofortification of cassava for Sub-Saharan Africa. Annual Review of Plant Biology, 62, pp. 251-272.
Gbadegesin, M. A. and Beeching, J. R., 2011. Highly heterogeneous Ty3/Gypsy-like retrotransposon sequences in the genome of cassava (Manihot esculenta Crantz). African Journal of Biotechnology, 10 (20), pp. 3951-3963.
Bull, S. E., Ndunguru, J., Gruissem, W., Beeching, J. R. and Vanderschuren, H., 2011. Cassava: constraints to production and the transfer of biotechnology to African laboratories. Plant Cell Reports, 30 (5), pp. 779-787.
Blagbrough, I. S., Bayoumi, S. A. L., Rowan, M. G. and Beeching, J. R., 2010. Cassava: an appraisal of its phytochemistry and its biotechnological prospects. Phytochemistry, 71 (17-18), pp. 1940-1951.
Gbadegesin, M. A. and Beeching, J., 2010. Enhancer/Suppressor mutator (En/Spm)-like transposable elements of cassava (Manihot esculenta) are transcriptionally inactive. Genetics and Molecular Research, 9 (2), pp. 639-650.
Bayoumi, S. A. L., Rowan, M. G., Beeching, J. R. and Blagbrough, I. S., 2010. Constituents and secondary metabolite natural products in fresh and deteriorated cassava roots. Phytochemistry, 71 (5-6), pp. 598-604.
Bull, S. E., Owiti, J. A., Niklaus, M., Beeching, J. R., Gruissem, W. and Vanderschuren, H., 2009. Agrobacterium-mediated transformation of friable embryogenic calli and regeneration of transgenic cassava. Nature Protocols, 4 (12), pp. 1845-1854.
Bayoumi, S. A. L., Rowan, M. G., Beeching, J. R. and Blagbrough, I. S., 2008. Investigation of biosynthetic pathways to hydroxycoumarins during post-harvest physiological deterioration in cassava roots by using stable isotope labelling. ChemBiochem, 9 (18), pp. 3013-3022.
Bayoumi, S. A. L., Rowan, M. G., Blagbrough, I. S. and Beeching, J. R., 2008. Biosynthesis of scopoletin and scopolin in cassava roots during post-harvest physiological deterioration: The E-Z-isomerisation stage. Phytochemistry, 69 (17), pp. 2928-2936.
Gbadegesin, M. A., Wills, M. and Beeching, J. R., 2008. Diversity of LTR-retrotransposons and Enhancer/Suppressor Mutator-like transposons in cassava (Manihot esculenta Crantz). Molecular Genetics and Genomics, 280 (4), pp. 305-317.