"Shellshock" Developing methods of using chitin to reduce potato cyst nematode populations

Potato cyst nematodes (PCN) (Globodera spp.) occupy c.48% of the potato growing area in England and Wales and 13.2% of production land in Scotland. The concerns associated with PCN, include long-term survival in soil (20+ years), severe yield loss in unprotected crops (up to 80%), legislation surrounding seed production and diminishing chemical control options. Various alternative crop protection options are being investigated including biofumigants, trap crops and soil amendments such as chitin. Chitin is present in several industry by-products including shellfish waste composed of crustaceans such as langoustines, crabs and lobsters, spent mushroom compost (SMC) and the frass and pupal cases associated with black soldier fly (BSF) production. Chitin and chitosan (deacetylated form of chitin) are thought to suppress pathogens by 1. Increasing populations of microbes that secrete chitinase; fungi and nematodes contain chitin in their cell walls and eggshells respectively, 2. Causing the release of ammonia, which is toxic to pests and pathogens, 3. Enhancing the activity of antagonists such as Bacillus subtilis, which secrete chitinase, 4. Inducing plant resistance by acting as a plant defense elicitor. This project seeks to evaluate the potential of chitinous amendments in the suppression of PCN. Specific objectives are 1. Evaluate the ability of chitinous soil amendments to suppress PCN populations in controlled conditions and within potato rotations, 2. Develop and optimise the method for evaluating chitinase activity, 3. Investigate mechanisms of PCN suppression using the chitinase assay discussed above and/or measurement of ammonia. 4. Develop methods for optimising and combing the use of chitinous soil amendments with other non-chemical methods, including applications with biopesticides and 5. Evaluate, the impact of organic soil amendments on soil health using bioindicators such as collembola and/or earthworms