Plant Diseases and Vectors

The main objective of the Plant Diseases and Vectors group is to advance high-quality research on global, emerging or invasive agricultural pests and diseases that cause poverty and undermine the food security in developed and developing countries. We aim to utilise the knowledge and intellectual property (IP) gained from this research to develop novel environmentally sustainable solutions, which involve modelling, forecasting, and novel pest & disease management technologies. The development and promotion of integrated pest management (IPM) systems is at the core of the EC's approach to decreasing use of pesticides.
We underpin our work with plant science and microbiology research and aim to provide concerted application of natural and social sciences to reduce the losses caused by pests and diseases. This will improve food security through profitable farming which provides safe and healthy food, while sustaining biodiversity, protecting the environment and decreasing agriculture's carbon footprint. The Group's research activities are centred around:

• Basic research on plant science and microbes including agricultural pests and diseases and the interaction with their hosts
• Molecular biology of plant development, disease and pest organisms
• Development of diagnostic systems for pest and disease organisms
• Capacity-building in IPM and aspects of natural resource management
• Contributing to policy on pest management in agriculture and natural resource conservation
• Adaptive research on IPM component technologies
• Research and development on integrating IPM component technologies into practical and cost-effective pest management systems
• Research and development on alternatives to synthetic biocides in pest and disease management with particular expertise in:
  • Insect viruses as biocontrol agents
  • GM crops in IPM
  • Exploring mechanisms of resistance to pests and diseases in host plants
• Social science research to support sustainable agriculture and enhanced ecosystem services.
• Tissue culture, chemo and thermos-therapies, and virus indexing (PCR and qPCR) technologies for generating virus-free planting material for better crop production
• Developing clean and better seed systems (eg. Sweet potato) by linking seed producers to research and growth markets
• Understanding the mechanisms of virus disease resistance and resistance gene mining using RNA-Sequencing technologies, particularly in cassava
• Exploring insect microbiome diversity by next generation sequencing technologies such as metagenome sequencing for understanding insect-bacterial infections, particularly in whiteflies.

• Dual-resistant cassava for climate resilience, economic development and increased food security of smallholders in eastern and southern Africa (DualCassava). Contact Professor Maruthi Gowda m.n.maruthi@gre.ac.uk
  https://www.nri.org/latest/news/2018/making-cassava-doubly-resilient-nri-tackles-el-nino-and-cassava-diseases
• Building Local Capacity for Surveillance Diagnosis, Characterisation and Control of Cassava Viruses in Northern Nigeria. Contact Professor Maruthi Gowda m.n.maruthi@gre.ac.uk
• Transcriptome analysis of virus-infected cassava and yeast-two-hybrid assays for resistance gene mining. Contact Professor Maruthi Gowda m.n.maruthi@gre.ac.uk
• African cassava whitefly project: outbreak causes and sustainable solutions. Contact Professor John Colvin J.Colvin@greenwich.ac.uk, http://cassavawhitefly.org/
  • Understanding whitefly bacterial infections and exploring its microbiome diversity using metagenome sequencing
  • Identifying resistance to the whitefly Bemisia tabaci in wild cassava accessions, Latin American genotypes and African land races
• Developing novel biopesticide formulation technology for major Lepidopteran crop pests. Contact David Grzywacz D.Grzywacz@greenwich.ac.uk
• Evolutionary biology: roles of novel membrane regulators of plants, microbes and organelles. Contact Elinor Thomposn e.thompson@greenwich.ac.uk

• Mr Sumesh Kakkunnath
  Sumesh is also from Kerala India. Aim of his PhD is to understand the mechanism of disease resistance in cassava for the Cassava brown streak virus. Sumesh will use yeast two hybrid system for identifying plant proteins interacting with the viral proteins, and in particular VPg and CP. His studies are funded by the University of Greenwich’s Vice Chancellor’s scholarship scheme for 2014–17. Sumesh has a Masters in Biotechnology from the University of Agricultural Sciences, Bengaluru India, and he’s an Associate Professor at the University of Agricultural Sciences, Dharawad India.

• Ms Jackie Atim
  Jackie is also from Uganda joined ACWP in November 2015. Her PhD will be on identifying whitefly resistance in the local and introduced cassava germplasm from Uganda and Columbia, respectively. She will then try to identify whitefly resistance genes using next generation sequencing technologies. Jackie obtained a BVS in Agriculture with Education at Kyambogo University in Uganda, MSc in Plant Biotechnology (Molecular Plant Breeding and Pathology) at Wageningen University Netherlands. She also had one year training in developmental orientated Plant Biotechnology and Biosafety from Martin Luther University Halle Germany.
• Ms Hajar El Hamss
  Hajar is from Morocco. She has a first master degree with honours in pest and disease management from ENAM (Ecole National d Agriculture de Meknes) Morocco. She completed a second MSc in Agriculture for sustainable development with distinction at NRI. She has also joined ACWP. Her PhD is on cassava whitefly endosymbionts which is expected to start in December 2015. Hajar will use a combination of insect bioassays and molecular tools to understand the role of endosymbionts on insect population development and the dynamics of cassava whitefly in African countries.
  
  
• Ms Siji Philip Kavil
  Siji is from Kerala, India. She is one of our VC scholarship students for 2015-16 and is expected to start before the end of the year. Her PhD will be on developing markers and validation of cassava genes conferring resistance to cassava brown streak virus. She has a BSc in Biotechnology from Bharathiar University Kerala, and MSc in Biotechnology from Bharathdasan University, Tamilnadu. Siji also has eight years of research experience in plant molecular biology at the University of Agricultural Sciences in Karnataka India.
  
  
• Ms Erica Ngwensang
  Erica is from Cameroon. She obtained an undergraduate degree in Environmental Sciences at University of Buea 2012. She then moved to Anglia Ruskin University, London in 2014 to undertake her postgraduate degree in International project management. Erica is now undertaking a PhD on the identification and characterisation of cassava genes conferring resistance to cassava mosaic virus.
  
  
  
• Mr Ahmad Hamza Balarabe
  Ahmad is from Kebbi state northern Nigeria. He has obtained a Masters in Natural Resources from the University of Greenwich in 2008 and he has come back to do PhD on ‘Molecular characterization, surveillance and identifying sources of resistance to cassava mosaic viruses in Nigeria’. He’s conducting field research in Nigeria for 1.5 years on cassava virus disease surveys and epidemiology, and the remaining 1.5 years will be spent at NRI in the UK on virus diagnosis, diversity and resistance mechanisms.
  
  
• Ms Happyness Gabriel Mollel
  Happyness from Tanzania is a visiting PhD student in African Cassava whitefly Project (ACWP). She is registered at the University of Malaga (UMA), Spain from October, 2015 under the supervision of Dr Jesus Navas-Castillo. The main aim of her PhD studies is to determine biological species boundaries of the African cassava whitefly, B. tabaci and virus interaction, and also to understand the effect of viruses and host plant on whitefly biology. Part of her research work will be conducted at NRI, UK. Her studies will focus on reciprocal crossing experiment of Ipomea indica SSA2 from Spain and cassava whitefly, B. tabaci from East Africa. She has a MSc in Science (Molecular and Cell Biology) from the University of Witwatersrand, Johannesburg, South Africa, and BSc in Biotechnology and Laboratory Science from Sokoine University of Agriculture, Morogoro, Tanzania. Happyness has eight years of research experience in molecular plant virology at Mikocheni Agriculture Research Institute (MARI), Tanzania.
  
  
• Mr Hastings Musopole
  Hastings is from Malawi. He has obtained a Masters, from the University of Free State from South Africa, and joined NRI for PhD in 2018 in the project ‘DualCassava’. His PhD is titled ‘Socio-economic Impact of drought and cassava virus diseases in Malawi, and the identification of disease resistant cassava using molecular techniques’, is a combination of social and biological sciences to understand how farmers are coping with the dual effects of drought and diseases to their crop plants in Malawi. He spends about 2 years in Malawi carrying out field research and over 1 year in the UK carrying out lab-based molecular research.
  
  
• Mohamed Said
  Mohamed Said is a graduate from MSA College in Cairo, Egypt. His PhD is jointly conducted with the group of Professor Jeremy Everett, on the detoxification response of the model organism C. elegans. His work includes a collaboration with University College London researchers interested in organelle biology and lifespan.

• Dale Harrison
  Dale Harrison is a Greenwich biology graduate who worked in postharvest science locally. His PhD is a molecular biology study of novel regulators of plant carbon metabolism, stress and fertility. He works in the model plant Arabidopsis and the model chloroplast Synechocystis. His studies are funded by a University of Greenwich Vice Chancellor's Scholarship.

• Arwa Selim
  Arwa Selim is a graduate from MSA College in Cairo, Egypt. Her PhD is centred on the biological roles of microbial membrane transporters including their potential for exploitation in biotechnology.
  
  

• Professor Susan E Seal
• Dr Goncalo D R Silva
• Professor John Colvin
• Professor Maruthi M N Gowda
• Dr Rekha Swamy
• Dr Sophie Bouvaine
• Dr Svenning Moller

Affiliates

• Dr Louise Abayomi

• Ferrara BT, Thompson E, 2020. Multidrug and efflux transporters of the model microbe Dictyostelium discoideum. Access Microbiology 2 (in press).
• He M, Tang S, Cheke RA, 2020. A Holling type II discrete switching host-parasitoid system with a nonlinear threshold policy for integrated pest management. Discrete Dynamics in Nature and Society (in press).
• Nwezeobi J, Onyegbule O, Nkere C, Onyeka J, van Brunschot S, Seal S and Colvin J, 2020. Cassava whitefly species in eastern Nigeria and the threat of vector-borne pandemics from East and Central Africa. PLoS ONE, 15 (5):e0232616.
• Parry HR, Kalyebi A, Bianchi F, Sseruwagi P, Colvin J, Schellhorn N, Macfadyen S, 2020. Evaluation of cultural control and resistance‐breeding strategies for suppression of whitefly infestation of cassava at the landscape scale: a simulation modelling approach. Pest Management Science. ISSN 1526-498X (Print), 1526-4998.
• Wang HL, Lei T, Wang XW, Maruthi MN, Zhu DT, Cameron SL, Rao Q, Shan HW, Colvin J, Liu YQ, Liu SS, 2020. A newly recorded Rickettsia of the Torix group is a recent intruder and an endosymbiont in the whitefly Bemisia tabaci. Environmental Microbiology, 22:1207-1221.
• Cheke RA, Sidatt EHM, 2019. A review of alternatives to fenthion for quelea bird control. Crop Protection 116: 15-23.
• Hally HM, Hamss HE, Simiand C, Maruthi MN, Colvin J, Omongo CA, Delatte H, 2019. What has changed in the outbreaking populations of the severe crop pest whitefly species in cassava in two decades? Scientific Reports, 9:14796.
• Maruthi MN, Whitfield C, Otti G, Tumwegamire S, Kanju E, Legg JP, Mkamilo G, Kawuki R, Benesi I, Mhone A, Zacarias A, Munga T, Mwatuni F, Mbugua E, 2019, A method for generating virus-free cassava plants to combat viral disease epidemics in Africa. Physiological and Molecular Plant Pathology 105:77-87.
• Milledge JJ, Thompson EP, Sauvetre A, Schroeder P, Harvey P, 2019. Novel developments in biological technologies for wastewater processing. In: Galanakis, Charis M. and Agrafioti, Evita, (eds.) Sustainable Water and Wastewater Processing. Elsevier, pp. 239-278. ISBN 978-0128161708 (doi:https://doi.org/10.1016/B978-0-12-816170-8.00008-9)
• Tang S, Liang J, Xiang C, Xiao Y, Wang X, Wu J, Li G, Cheke RA, 2019. A general model of hormesis in biological systems and its application to pest management. Journal of the Royal Society Interface 20190468.
• Thompson E, Ferrara BT, 2019. A method for visualising fluorescence of polyphenolic therapeutics in vivo in the model eukaryote, Dictyostelium discoideum. BioTechniques, 66 (2). pp. 65-71.
• Thompson E, Rafiq M, 2019. The Dictyostelium rhomboid proteases and mitochondrial disease. Access Microbiology 1 (1A):452
• Tian Y, Tang S, Cheke RA, 2019. Dynamic complexity of a predator-prey model for IPM with nonlinear impulsive control incorporating a regulatory factor for predator releases. Mathematical Modelling and Analysis 24: 134-154. (https:/doi.org/10.3846/mma.2019.010).
• Vyskočilová S, Seal S, Colvin J, 2019. Relative polyphagy of “Mediterranean” cryptic Bemisia tabaci whitefly species and global pest status implications. Journal of Pest Science, 92 (3). pp. 1071-1088.
• Wang HL, Lei T, Xia W-Q, Cameron SL, Liu Y-Q, Zhang Z, Maruthi MN, De Barro P, Navas-Castillo J, Omongo CA, Delatte H, Lee K-Y, Patel MV, Krause-Sakate R, Ng J, Wu S-L, Fiallo-Olivé E, Liu S-S, Colvin J & Wang X-W, 2019. Insight into the microbial world of Bemisia tabaci cryptic species complex and its relationships with its host. Scientific Reports 9, Article number: 6568.
• Weinrich T, Hoh Kam J, Ferrara BT, Thompson EP, Mitrofanis J, Jeffery G, 2019. A day in the life of mitochondria reveals shifting workloads. Scientific Reports 9:13898.
• Cheke RA, 2018. New pests for old as GMOs bring on substitute pests. Proceedings of the National Academy of Sciences of the USA 115: 8239-8240.
• Ghosh S, Bouvaine S, Richardson SCW, Ghanim M, Maruthi MN, 2018. Fitness costs associated with infections of secondary endosymbionts in the cassava whitefly species Bemisia tabaci. Journal of Pest Science 91:17–28.
• Fennell J, Veys C, Dingle J, Nwezeobi J, van Brunschot S, Colvin J, Grieve B, 2018. A method for real-time classification of insect vectors of mosaic and brown streak disease in cassava plants for future implementation within a low-cost, handheld, in-field multispectral imaging sensor. Plant Methods, 14 (1). ISSN 1746-4811
• Liang, J., Tang, S. & Cheke, R.A. (2018) A discrete host-parasitoid model with evolution of pesticide resistance and IPM strategies. Journal of Biological Dynamics 12: 1059-1078.
• Macfadyen S, Paull C, Boykin LM, De Barro P, Maruthi MN, Ghosh S, Otim M, Kalyebi A, Vassão DG, Sseruwagi P, Tay WT, Delatte H, Seguni Z, Colvin J, Omongo CA, 2018. Cassava whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), in sub-Saharan African farming landscapes: a review of the factors determining abundance. Bulletin of Entomological Research, 108 (5). pp. 65-582.
• Malka O, Santos-Garcia D, Feldmesser E, Sharon E, Krause-Sakate R, Delatte H, van Brunschot S, Patel M, Muhindira PV, Mugerwa H, Seal S, Colvin J, Morin S, 2018. Species-complex diversification and host-plant associations in Bemisia tabaci : a plant-defense, detoxification perspective revealed by RNAseq analyses. Molecular Ecology, 27 (21). pp. 4241-4256.
• Masinde EA, Mkamillo G, Ogendo JO, Hillocks R, Mulwa RMS, Kimata B, Maruthi MN, 2018. Genotype by environment interactions in identifying cassava (Manihot esculenta Crantz) resistant to cassava brown streak disease. Fields Crops Research 215: 39-48.
• Mugerwa H, Seal S, Wang HL, Patel MV, Kabaalu R, Omongo CA, Alicai T, Tairo F, Ndunguru J, Sseruwagi P, Colvin J, 2018. African ancestry of New World, Bemisia tabaci-whitefly species. Scientific Reports, 8 (1):2734.
• Tian Y, Tang S, Cheke RA, 2018, Nonlinear state-dependent feedback control of a pest-natural enemy system. Nonlinear Dynamics 94: 2243–2263.
• Vyskočilová S, Tay WT, van Brunschot S, Seal S, Colvin J, 2018. An integrative approach to discovering cryptic species within the Bemisia tabaci whitefly species complex. Scientific Reports, 8:10886.
• Maruthi MN, Jeremiah SC, Mohammed IU, Legg JP, 2017, The role of the whitefly, Bemisia tabaci (Gennadius), and farmer practices in the spread of cassava brown streak ipomoviruses. Journal of Phytopathology 165:707–717.
• Xiang C, Tang S, Cheke RA, Qin W, 2016. A locust phase change model with multiple switching states and random perturbation.  International Journal of Bifurcation and Chaos 26: 1630037.