Benchmarking water limited yield of cereal crops on major soil types across Eyre Peninsula

This research aims to determine in which situations extra fertilisation can bring benefits to growers in 14 different Eyre Peninsula (EP) environments.Every season, growers need to make choices over limited resources in order to optimise their profitability. Soil type and water represent two of the key limiting resources which define the grain yield potential of a paddock. The unpredictability of growing season rainfall patterns restricts in-season fertiliser applications for EP growers, due to the associated high economic risks. As a risk management strategy, growers often apply lower rates of nutrients than required to achieve the water limiting yield potential (Sadras and Roget 2004, Monjardino et al. 2013). Therefore, less than optimum nutrient rates are applied in many instances, and maximum grain yield gains are not reached on occasions where opportunities have existed. Understanding soil water and nutrient dynamics can be useful to determine when in-season extra fertiliser applications are worth the investment in EP dryland farming systems.This study used a subset of the Eyre Peninsula Agricultural Research Foundation (EPARF) soil moisture probe network locations to benchmark the water limited yield potential and determine the achievable grain yield of cereals crops across major soil types of EP.