Soil exploration by sorghum root systems in wide row cropping systems

Wide and ‘skip row’ row configurations have been used as a means to improve yield reliability in grain sorghum production. However, there has been little effort put to design of these systems in relation to optimal combinations of root system characteristics and row configuration, largely because little is known about root system characteristics. The studies reported here aimed to determine the potential extent of root system exploration in skip row systems. Field experiments were conducted under rain-out shelters and the extent of water extraction and root system growth measured. One experiment was conducted using widely-spaced twin rows grown in the soil. The other experiment involved the use of specially constructed large root observation chambers for single plants. It was found that the potential extent of root system exploration in sorghum was beyond 2m from the planted rows using conventional hybrids and that root exploration continued during grain filling. Preliminary data suggested that the extent of water extraction throughout this region depended on root length density and the balance between demand for, and supply of, water. The results to date suggest that simultaneous genetic and management manipulation of wide row production systems might lead to more effective and reliable production in specific environments. Further study of variation in root-shoot dynamics and root system characteristics is required to exploit possible opportunities.

National whoppercropper - risk management discussion support software

It is a paradox that in a country with one of the most variable climates in the world, cropping decisions are sometimes made with limited consideration of production and resource management risks. There are significant opportunities for improved performance based on targeted information regarding risks resulting from decision options. WhopperCropper is a tool to help agricultural advisors and farmers capture these benefits and use it to add value to their intuition and experience. WhopperCropper allows probability analysis of the effects of a range of selectable crop inputs and existing resources on yield and economic outcomes. Inputs can include agronomic inputs (e.g crop type, N fertiliser rate), resources (e.g soil water at sowing), and seasonal climate forecast (SOI phase). WhopperCropper has been successfully developed and refined as a discussion-support process for decision makers and their advisers in the northern grains region of Australia. The next phase of the project will build on the current project by extending its application nationally and enhancing the resource management aspects. A commercial partner, with over 800 advisor clients nationally, will participate in the project.