Use of chemical protective products to change the ability of wheat to tolerate frost

Abstract

Frost is a large issue limiting cereal production across the Australian wheat-belt. Successful frost risk management requires an integrated approach involving many aspects of the farming system, such as sowing time, crop/cultivar selection, stubble management and plant nutrition. A number of commercial chemical products have become available in recent times offering potential crop protection to frost damage. During 2014 at Mintaro, South Australia, four protectant products (anti-transpirant and biochemical products) were applied and one plant growth regulator, Trinexapac-ethyl to wheat plots sown at seven weekly intervals to assess their potential to alleviate frost damage. Several frost events occurred during the growing season. The degree of frost damage varied across each time of sowing corresponding to frost events at susceptible stages of plant development. Of the chemical protectants tested, none provided any significant reduction in frost induced sterility or gains in yield compared to the untreated control. However, the Trinexapac-ethyl increased the sensitivity of wheat to frost. Average frost induced sterility increased from 42% of the untreated control to 51% when applied during stem elongation. This difference in sterility was also reflected in grain yield as the same treatment was 8% lower yielding than untreated plots. Preliminary results of this study suggested none of the tested chemical anti-transpirant or biochemical products offered any significant improvement in frost tolerance.