Analysis of soil eDNA functional genes: potential to increase profitability and sustainability of pastoral agriculture

Management of soil biological resources to optimise plant production, efficiency of nutrient inputs, and system sustainability is emerging as an opportunity for pastoral agriculture. To achieve these goals, suitable tools that can assess the functional state of the soil ecosystem must be developed, and standardised approaches to their application adopted. Towards this end, we have undertaken comprehensive analysis of environmental DNA (eDNA) obtained from 50 pastoral soils based on a high-density functional microarray, GeoChip5. When combined with soil, environmental, and management metadata, the information will provide insights into soil biological processes spanning greenhouse gas emissions, through to natural suppression of plant root diseases. To provide an example of a structured work-flow of analysis in a pastoral system context, we analysed the GeoChip data using a combination of approaches spanning and routine univaraite methods through to more complex multivariate and network-based analysis. From these, the opportunities for application of eDNA approaches (GeoChip or others) to deliver outcomes for pastoral agricultural in New Zealand are discussed.