Dr Hayley Norman1, Mr Matt Wilmot1, Ms Elizabeth Hulm1, Paul Young1, Mr Josh Hendry1, Mr Andrew Toovey1, Dr Dean Thomas1
1CSIRO,
Biography:
Hayley is a farming systems scientist who focusses on livestock and feedbase production within mixed farming systems. Her key research interests include improvement and utilisation of native shrubs, feeding value of annual legumes, saline and arid farming systems and development of near infrared spectroscopy tools to predict feeding value, intake and livestock performance.
Abstract:
Australian native shrubs from the Chenopodiaceae family are broadly adapted to dry, saline and/or nutrient deficient conditions. During the last two decades, there has been significant investment in the identification of shrub genotypes that persist and provide key nutrients that are scare in summer and during droughts. Economic studies demonstrate that these shrubs can lift whole-farm profitability, reduce the cost of livestock production and reduce whole-farm risk by buffering feed supply during poor seasons. Other benefits include better use of rainfall to manage salinity, shade and shelter for livestock, vitamin E and plant secondary compounds that may reduce methane and gut parasites. Many species are productive on marginal soils, so adoption comes with a lower opportunity cost when compared to other perennial systems.
The aim of this project was to compare accessions of the most promising eight shrub species for biomass production, relative palatability and nutritional value on three farms across WA and SA. Replicated plots of mixed shrubs and adjacent pastures or crop stubbles, were grazed with Merino sheep to determine wool growth, condition score and live weight change. Systems modelling was used to quantify economic benefits and identify targets for plant improvement.
There was significant variation in plant productivity traits, both biologically and economically, and the data has been used for in the selection of improved commercial lines of Atriplex nummularia (oldman saltbush) and Rhagodia preissii.