Ewen MullinsResearch Officer
For centuries, farmers have been improving and modifying their crops. Through the process of selective breeding, specific traits are identified and a hybrid line is created that expresses the desired agronomic character (e.g. high yield, disease resistance). This conventional form of breeding has had great success but by its nature has also imposed many restrictions. Modern day biotechnology provides a means to accelerate this pace of discovery and over the last decade especially, the application of this science to crop improvement has provided a tremendous insight into its potential.
Now, through biotechnology, a gene of interest that originates in bacteria, fungi, another plant can now be inserted into the genome of a specific crop. As a consequence, certain crops now possess characteristics that previously would have been considered unattainable. For example; potato varieties have been developed with resistance to potato blight disease after the transfer of genes from a number of wild potato species taken from central America, while 'Golden Rice' has been generated with elevated levels of vitamin A after the transfer of a number of daffodil genes into a commercial rice variety to combat childhood illnesses.
Though potentially advantageous, the production of these engineered plants has invoked public concern, in regard to the perceived environmental impacts and other issues associated with their coexistence with conventional and organic crop systems. Our research is focussed on addressing these concerns by generating Irish-specific datasets quantifying the cost-benefit of relevant traits that may be applicable to Irish agriculture.
At present, we are investigating the agri-environmental impact of a cisgenic potato line that has been developed with durable resistance to potato late blight disease; causative agent of the Irish Potato Famine. This work is being conducted at Oak Park under license by the EPA and is part of a larger European funded project ('AMIGA') to assess the impacts of GM crops on the agro-ecosystem. In parallel, we are conducting a gene discovery programme in wheat, with the goal of isolating genes that could provide durable resistance to the important leaf disease Septoria tritici blotch. This is critically important in light of the decreased efficacy of existing fungicide regimes against Septoria.
Separately, we have also developed a novel technology platform to transfer genes of interest into target crop species. Based on a non-Agrobacterium spp. our system (termed Ensifer-mediated transformation, 'EMT') bypasses the existing quagmire of patent restrictions that exist with current gene transfer techniques.
We have completed multiple studies on the issue of coexistence. One was focussed on developing cost-effective production measures for GM herbicide tolerant (GMHT) oilseed rape in coexistence with non-GM oilseed rape cultivars, while another has been on quanitfying the potential for gene flow (via pollen and/or seed) from potato crops. A parallel study assessed the environmental impact of Irish-specific GM crops using a novel biodiversity index (termed CINMa) which factors in the impact of a crop's management on different ecological zones (e.g. field, hedgerow etc...) through time. The objective of this work was to design a research methodology to assist in the completion of GM crop risk assessments as per the general surveillance component of EU legislation 2001/18.
- Delivering the potential of EMT - A novel gene transfer platform for crop biotechnology (RMIS 6603: funded through Enterprise Ireland Commercialisation Fund)
- Evaluating the potential of non-Agrobacterium spp. to facilitate gene transfer into main crops (RMIS 6188; funded through Science Foundation Ireland 2011 Research Frontiers Programme)
- Quantifying the potential of EMT, a novel gene transfer technology, to overcome the industrial challenge of
genotype dependency, which limits the engineering of multiple varieties of important crop species (RMIS 6808; funded through Science Foundation Ireland 2015 TIDA Programme)
- Breeding of wheat in order to enhance yield and disease resistance – mutation of the BRI1 brassinosteroid receptor gene (RMIS 6469, Project WheatEnhance, funded by the DAFM Research Stimulus Fund)
- Assessing and monitoring the impacts of GM crops on agro-ecosystems, 'AMIGA' (RMIS 6269, funded through the European Commission's 7th Framework)
- Cereal Improvement through Variety choice and understanding Yield Limitations (RMIS 6422, Project CIVYL, funded by the DAFM Research Stimulus Fund)
- Monitoring Pathogen Evolution for Sustainable Cropping (RMIS 6421, Project MonPESC, funded by the DAFM Research Stimulus Fund)
- CerealPath - Training in Innovative and Integrative Control of Cereal Diseases (RMIS 6790, funded by the H2020 Marie Curie Training Networks)
- VICCI - Virtual Irish Centre for Crop Improvement (RMIS 6741, funded by the DAFM Research Stimulus Fund)
- Hehir, G., Connolly, C., O’Driscoll, A., Lynch, J., Spink, J., Brown, J.K.M., Doohan, F. and Mullins, E. (2017). Temporal and spatial field evaluations highlight the importance of the pre-symptomatic phase in supporting strong partial resistance in Triticum aestivum against Zymoseptoria tritici. Plant Pathology, doi: 10.1111/ppa.12780
- Young, M. W., Mullins, E. and Squire, R. G. (2017). Environmental risk assessment of blight-resistant potato: use of a crop model to quantify nitrogen cycling at scales of the field and cropping system. Environmental Science and Pollution Research, p1-11, doi:10.1007/s11356-017-9769-8
- Ortiz, V., Phelan, S. and Mullins, E. (2016) A temporal assessment of nematode community structure and diversity in the rhizosphere of cisgenic Phytophthora infestans-resistant potatoes. BMC Ecology, 16:55 DOI: 10.1186/s12898-016-0109-5
- Thorne, F., Fox, S., Mullins, E. and Wallace, M. (2016). Consumer Willingness-to-Pay for Genetically Modified Potatoes in Ireland: An Experimental Auction Approach. International Journal of Agribusiness, DOI: 10.1002/agr.21477
- Rathore, D., Doohan, F. and Mullins, E. (2016). Capability of the plant-associated bacterium, Ensifer adhaerens strain OV14, to genetically transform its original host Brassica napus. Journal of Plant Biotechnology – Plant Cell and Tissue Organ Culture, DOI:10.1007/s11240-016-1032-3
- Ali, S.S., Nugent, B., Mullins, E. and Doohan, F. (2016). Fungal-mediated consolidated bioprocessing: the potential ofFusarium oxysporum for the lignocellulosic ethanol industry. Applied Microbiology and Biotechnology, 2016, 6:13.
- Collinge, D.B., Mullins, E., Jensen, B. and Jorgensen, H.J.L. (2016). The status and prospects for biotechnological approaches for attaining sustainable disease resistance. In: Plant Pathogen Resistance Biotechnology (Collinge, D, Ed.), Wiley Publishers, ISBN: 978-1-118-86776-1.
- Zuniga-Soto, E., Mullins, E. and Dedicova, B. (2015). Ensifer-mediated transformation: an efficient non-Agrobacterium protocol for the genetic modification of rice. SpringerPlus, Vol. 4, Issue 1.
- Rathore, D., Lopez-Vernaza, M., Doohan, F., O'Connell, D., Lloyd, A. and Mullins, E. (2015). Profiling antibiotic resistance and electro-transformation potential of Ensifer adhaerens OV14; a non-Agrobacterium species capable of efficient rates of plant transformation. FEMS Microbiology Letters,
- Vary, Z., Mullins, E., McElwain, J. and Doohan, F. (2015). The severity of wheat diseases increases when plants and
pathogens are acclimatized to elevated carbon dioxide. Global Change Biology, doi: 10.1111/gcb.12899
- Phelan, S., Fitzgerald, T., Grant, J., Byrne, S., Meade, C. and Mullins, E. (2015). Propensity for seed-mediated gene flow from potato crops and potential consequences for the coexistence of GM and non-GM potato systems. European Journal of Agronomy, Vol. 67, 52-60.
- O'Driscoll, A., Doohan, F. and Mullins, E. (2015). Exploring the utility of Brachypodium distachyon as a model pathosystem for the wheat pathogen Zymoseptoria tritici. BMC Research Notes, 8:132.
- Mullins, E. (2014). Engineering for disease resistance: persistent obstacles clouding tangible opportunities. Pest Management Science, Vol. 71 (5), 645-651.
- O’Driscoll, A., Kildea, S., Doohan, F., Spink, J. and Mullins, E. (2014). The wheat–Septoria conflict: a new front opening up?. Trends in Plant Science (in press) http://dx.doi.org/10.1016/j.tplants.2014.04.011
- Rudder, S,. Doohan, F,. Creevy, C,. Wendt, T. and Mullins, E. (2014). Genome sequence of Ensifer adhaerens OV14 provides insights into its ability as a novel vector for the genetic transformation of plant genomes. BMC Genomics.2014, 15:268, DOI: 10.1186/1471-2164-15-268
- Hennessy, R., Doohan, F. and Mullins, E. (2013). Generating phenotypic diversity in a fungal biocatalyst to investigate alcohol stress tolerance encountered during microbial cellulosic biofuel production. PLOS One,http://dx.plos.org/10.1371/journal.pone.0077501
- Ali, S.S., Khan, M., Mullins, E. and Doohan, F. (2013). Identification of Fusarium oxysporum Genes Associated with Lignocellulose Bioconversion Competency, Bioenergy Research, DOI 10.1007/s12155-013-9353-0.
- Collier, M. and Mullins, E. (2013). Potential for longevity of novel genetically modified herbicide-tolerant traits in the Irish landscape. Irish Geography, DOI:10.1080/00750778.2013.775768
- Ali, S.S., Nugent, B., Mullins, E. and Doohan, F. (2013). Insights from the fungus Fusarium oxysporum point to
high affinity glucose transporters as targets for enhancing ethanol production from lignocellulose. PLOS One, January, Volume 8, Issue 1, e54701.
- Collier, M. and Mullins, E. (2012) Assessing the impact of pollen-mediated gene flow from GM herbicide tolerant Brassica napus into common wild relatives in Ireland. Biology and Environment, Proceedings of the Royal Irish Academy, Vol. 112B, Issue 3, 257 - 266.
- Spink, J., Mullins, E. and Berry, P. (2012) Potential for Yield Improvement. In: Sayigh A (ed.) Comprehensive Renewable Energy, Vol. 5, p. 293-303. Oxford: Elsevier, ISBN: 978-0-08-087872-0.
- Ali, S.S., Khan, M., Mullins, E. and Doohan, F. (2012). The effect of wheat genotype on ethanol production from straw and the implications for multifunctional crop breeding. Biomass and Bioenergy, Vol.42, 1-9.
- Ali, S.S., Khan, M., Fagan, B., Mullins, E. and Doohan, F. (2012). Exploiting the inter-strain divergence of Fusarium oxysporum for microbial bioprocessing of lignocellulose to bioethanol. Applied Microbiology and Biotechnology Express, 2:16-19.
- Wendt, T., Doohan, F and Mullins, E. (2012). Production of Phytophthora infestans-resistant potato (Solanum tuberosum) utilising Ensifer adhaerens OV14. Transgenic Research, 21(3), 567-578.
- Wendt, T., Doohan, F., Wincklemann, D. and Mullins, E. (2011). Gene transfer into Solanum tuberosum via Rhizobium spp.Transgenic Research, 20(2), 377-386.
- Tricault, Y., Fealy, R., Colbach, N. and Mullins, E. (2011). Towards an optimal management regime to facilitate the coexistence of GM herbicide tolerant and non-GM oilseed rape. European Journal of Agronomy, 34, 26-34.
- Wendt, T. and Mullins, E. (2011). Future challenges and prospects. In: Genetics, Genomics and Breeding of Potato (Eds. J. Bradeen and C. Kole), CRC Press, Baton Rouge, ISBN: 9781578087150.
- Petti, C., Wendt, T., Meade, C. and Mullins, E. (2010). Evidence of genotype dependency within Agrobacterium tumefaciens in relation to the integration of vector backbone sequence in transgenic Phytophthora infestans-tolerant potato. Journal of Bioscience and Bioengineering, 107(3), 301-306.
- O’Brien, M and Mullins, E. (2009). Relevance of GM crops in light of future environmental and leglislative challenges. Annals of Applied Biology, 154, 323-340.
- O’Brien, M., Spillane, C., Meade, C. and Mullins E. (2008). An insight into the impact of arable farming on Irish biodiversity: A scarcity of studies hinders a rigorous assessment. Biology and Environment, Proc. of Royal Irish Academy, 108, 97–108.
- Petti, C., Meade, C., Downes, M and Mullins, E. (2007). Facilitating coexistence by tracking gene dispersal in conventional potato systems with microsatellite markers. Environmental Biosafety Research 6, 223-231.
- Ryan, E., Meade, C., Mullins, E., Burke, J. and Downes, M. (2007). Tracing field hybridisation in ryegrass species using microsatellite and morphological markers. Environmental Biosafety Research, 5, 106-118.
- Mullins, E., Milbourne, D., Petti, C. Doyle-Prestwich, B.M. and Meade, C. (2006). Potato in the age of biotechnology. Trends in Plant Science, 11, 254-260.
- Flannery, M-L., Meade, C.M. and Mullins, E. (2005). Employing a composite gene-flow index to numerically quantify a crop’s potential for gene flow: an Irish perspective. Environmental Biosafety Research, 1, 29.
- Meade, C. and Mullins, E. (2005). GM crop cultivation in Ireland: Ecological and Economical considerations. Biology and Environment, Proc. Royal Irish Academy, 105, 1, 33-52.
- Dheeraj Rathore - Expanding the potential of Ensifer-mediated transformation in crop species
- Jeroen Stellingwerf - Monitoring the evolution of Phytophthora infestans (late blight disease) against novel sources of genetic resistance
- Evelyn Zuniga – Investigating the genetic mechanisms underlying the efficacy of Ensifer-mediated transformation
- Ashok Govindan - Enhancing the operability of EMT: a novel gene transfer technology platform for crop biotechnology
- Atikur Rahman – Examining the ‘trade-off’ of genetic resistance to septoria tritici blotch disease in winter wheat.