The project aimed to characterise susceptibility to frost events at flowering in wheat and barley. Frost damage to crops can occur at any time but are most devastating close to flowering, as the pollen is particularly sensitive to extreme variations in temperature. Frost at flowering may lead to aborted florets, which results in reduced grain set.
Previous research in frost susceptibility in wheat and barley from across the country had mixed results. This could have been due to genetic or environmental variations, or possibly from experimental methods. This project is a continuation of a previous project that was successful in creating a standardised method for screening of frost induced sterility (FIS). This is now being used in the northern, southern and western GRDC cropping regions to allow for better comparisons between the different varieties of wheat and barley in the all production zones of Australia.
From humble beginnings of testing just three wheat varieties and eight barley varieties, in 2012, the project tested 108 varieties of wheat and 36 of barley at eight different times of sowing at a trial sites located at Dale, Western Australia from 2016–2020. Previous to that trials were located at Merredin, Wickepin and Aldersyde, near Brookton. Results from the project showed that under a severe frost (that is, -4.5°C or below), or multiple minor frosts (for example, several nights of -1 to -2°C), all wheat varieties tested were equally susceptible to FIS, resulting in up to 100% yield loss. It was also shown that barley was more tolerant then wheat to the minor frosts, but will succumb to FIS under severe conditions.
The results from this project have contributed to the rating and rakings of wheat and barley varieties across Australia that was released in February 2016 and available on the NVT website. The key messages were to first select varieties on performance and agronomic fit in your environment, then use the frost ratings to fine tune your risk management.
Acknowledgements
The Screening of Frost Tolerance in Cereals was supported by DPIRD and the Grains Research and Development Corporation UA00136, UA00162, DAW00234, UW00005 through the National Frost Initative.