Improved Wheat Yield with Silicon

A growing and more affluent population, rising demand for water, land and other natural resources, and increasingly unpredictable weather are putting pressure on the our ability to deliver food security, both now and into the future. We urgently need to find new ways to provide the 60% more food we are predicted to need by 2050 without damaging the agricultural ecosystem or increasing the inputs of water, fertiliser and pesticide. Addressing this challenge will require new inter-disciplinary and environmentally sustainable approaches to crop improvement. This PhD project will test the ability of silicon, one of the most abundant elements in soil, but often in a form not available to plants, to improve the yield of wheat, the most important crop in the UK, but one where average yield has not increased since the mid-1990s. Silicon is known to benefit crops by increasing growth and improving their resilience to abiotic stresses such as drought and biotic stresses such as herbivory or disease. Despite evidence of Si benefits to agriculture, little is known about their molecular basis - we lack quantitative assessments of the relationship between Si uptake and the benefits to wheat performance and how this relationship differs between different wheat genotypes. This project addresses this knowledge gap using an innovative combination of diverse wheat cultivars, including both modern high yielding and ancestral varieties, and new transgenic wheat lines, which over-express the main Si uptake mechanism. The student will determine the relationship between Si uptake and tolerance to drought, salinity and aphid herbivory in a range of wheat genotypes and test how overexpression of the main Si uptake system in wheat (TaLsi1) affects Si uptake and wheat performance. They will assess how TaLsi1 expression affects Si uptake and distribution within plant tissues and how this impacts on the yield and tolerance to drought, salinity and aphid herbivory of the transgenic lines. The successful student will receive training in state-of- the art molecular techniques, combined with plant biology and agro-ecology, all within an experimental system with the potential for real world impact in food security. They would gain experience of a range of disciplines, including molecular genetics, plant ecophysiology and plant ecology. They would also be trained in the use of the latest techniques in plant chemical and image analysis, including scanning electron microscopy and portable X-ray fluorescence spectroscopy.