description
- To sustainably feed our ever-growing population, it is imperative that we establish agricultural systems that are resilient to crop pests and diseases. Global food production is presently at an elevated risk to epidemics arising as a result of rapid pathogen evolution. Numerous recent examples of devastating disease occurrences underpinned by evolutionary changes in fungal pathogens exist. These epidemics were triggered by pathogen adaptation in the form of host jumps (e.g. Wheat Blast) and overcoming previously effective resistance (e.g. Ug99 Stem Rust). Such occurrences of pathogen adaptation underline the threat posed by rapid pathogen evolution on our food production systems. The danger posed by fungal pathogen evolution is further exacerbated by climate change which has led to non-native pathogens invading and thriving in parts of the world where they were previously not endemic. Crop diseases come with enormous economic cost to food production. For instance, it has been estimated that ~88% of the world's wheat production is vulnerable to yellow rust caused by the pathogen Puccinia striiformis f.sp. tritici and that this disease alone causes losses of wheat equivalent to US$979 million per year. It is not wheat alone that is under threat from diseases caused by the Puccinia rust fungi. Among the world's most cultivated cereals, 9 out of 10 are vulnerable to the genera Puccinia. This includes the UK's three most important cereal crops - wheat, barley and oats. Thus, it is vital that we protect UK agriculture from diseases caused by Puccinia fungi by developing methods for effectively combating these pathogens. Current approaches aimed at ensuring that our cereal crops are protected from diseases caused by Puccinia fungi generally tap into existing sources of plant disease resistance and largely utilise modifications of existing fungicide compounds. A robust long-term disease prevention strategy requires that we are able to rapidly combat both current and future strains of Puccinia fungi. The main limitation of current pathogen control approaches against Puccinia pathogens is the focus on pre-existing sources of resistance/activity. Therefore, there is a need to develop tailored control approaches that can quickly be engineered to combat pathogen adaptability. One possibility to accomplish this would be through the development of flexible biological and chemical control approaches that can be modified to target different aspects of fungal infection. To take this route, we need a comprehensive understanding of how diverse Puccinia fungi infect and cause disease on their cereal hosts but unfortunately such knowledge is currently lacking. Therefore, the overall aim of this fellowship is to develop a long-needed understanding of the mechanisms used by diverse Puccinia fungi to infect their cereal hosts and characterise the different stages in the progression of these infections. This will be achieved through the application of cutting-edge genomics and high-resolution microscopy technologies. With this knowledge in place, the potential of targeting these mechanisms for controlling the infection of wheat and barley by Puccinia fungi will also be explored. Through this fellowship I aim to: Objective 1 - Identify genes conserved in diverse cereal-infecting Puccinia species. Objective 2 - Determine which of these conserved genes function during the infection of wheat by different Puccinia species. Objective 3 - Evaluate whether disrupting these conserved infection genes affects the ability of Puccinia species to infect wheat and barley. At the end of the project, I aim to deliver a list of Puccinia genes that represent potential targets for developing novel methods of pathogen control. These target genes would be of particular interest to industry partners by providing the starting material required to develop novel fungicides that can protect our cereal crops from Puccinia fungi.