The Grains Research and Development Corporation (GRDC) has long acknowledged the complex constraint that frost exerts on grain production in Australia and amalgamated and enhanced frost projects into the National Frost Initiative (NFI) in 2014.
NFI focuses on wheat and barley, particularly wheat, as the dominant winter crop it underpins the sustainability of Australian farming systems. The NFI has been designed as an integrated multi-disciplinary initiative bringing diverse intellects to the problem (see table). Initially the NFI will run for five years, with a GRDC investment of around $4.0M per year. The NFI outcome is for “Australian cereal producers manipulating their farming system to minimise the impact of frost on crop yield and maximise seasonal profit”.
GRDC projects in the National Frost Initiative as at 1 January 2017.
Genetics
This program aims to:
- Introduce and evaluate new germplasm
Australian cereal varieties have a narrow genetic base so genetic resources from international collections are being imported and screened using methods developed by the University of Adelaide (UA). Material offering superior performance under frost to current varieties will be provided to Australian breeding programs. Additionally CSIRO are investigating whether improved performance of some varieties to frost in field and growth chamber studies is related to triggering of genuine frost tolerance genes. These studies are considering physiological characters in contrasting varieties, which is expected to help identify genetic markers of value to develop new, potentially frost tolerant varieties.
- Rank the frost tolerance/susceptibility of new germplasm, and current and near-release lines of wheat and barley:
Through the screening method developed by UA an interactive selection tool for wheat and barley varieties with reduced susceptibility to frost has been developed for growers (nvtonline.com.au/frost).
Management
This program evaluates the effectiveness of agronomic practices, both pre-sowing and in-crop to reduce frost impact.
Pre-sowing decisions are based on landscape and knowledge of frost incidence, variety selection and adoption of appropriate agronomic practices. The practices include fertiliser timing and amount, row spacing and orientation, seed rate and density, growth regulators, grazing management, delving/claying etc. The interactions between these practices are complex and an initial project identified those that have measureable influence on reducing the impact of frost on cereals. These practices (particularly stubble management; canopy management – including timing and amount of nitrogen, and interaction with seed rate; some work on PGR’s in high rainfall areas; and the value of different cereal crop types – barley, oats for grain/hay to minimise the impact of frost) are now being researched in more detail in a new national project which started in July 2016.
Several grower groups including BCG are involved in this project; trials are managed as ‘extensive’ (gathering information on farm to build a record of response to selected treatments) or ‘intensive’ (usually run with a grower group and/or research partner to gain a better understanding of mechanisms driving crop response to frost). All sites are instrumented with data loggers to record temperature at head height, and all use the standardised screening methods developed by UA.
Environment
To manage frost risk growers need good on-farm records of minimum temperature, an understanding of temperature variation across paddocks, reliable predictions of when a crop will flower for a given sowing time, and an understanding of the potential damage caused by different temperatures. A major CSIRO project in this program is exploring tools and technologies to generate accurate, user-friendly, spatial temperature information at a resolution consistent with the scales of farm and crop management. This work is complimented by another CSIRO project which is seeking to understand the synoptic patterns that cause frost in a region. This will help understand occurrence of individual frost events and clusters of events. Making sense of the climate drivers of damaging frosts will help assess if there is a basis for future prediction at a seasonal time scale.
