Email: abebayehu.geffersa@csiro.au

Genetic resistance provides an efficient means of controlling rust diseases of wheat. However, pathogen evolutionary adaptation, leading to the breakdown of resistance, is common and can cause damaging epidemics. This requires farmers to use higher-input methods for disease control, and ongoing investment in research and development associated with the breeding of wheat varieties with new forms of effective resistance.

However, there has been relatively little effort to quantify the overall economic benefits that farmers receive from effective resistance. This makes it difficult to accurately articulate to farmers the advantages of adopting new resistant varieties as opposed to using alternative control methods (e.g. fungicides), or for breeders and other stakeholders to understand the value associated with the development of new resistant germplasm.

In this paper, we examine the economic benefits of wheat genetic resistance to rust disease in Australian cropping systems. We start by introducing a flexible economic framework to quantify the benefits of resistance. Leveraging empirical data for 2021 cropping season—over 5,000 observations from the Australian wheat-rust systems—we (i) examine how rust-resistant wheat cultivars are adopted and replaced; and (ii) quantify the economic benefits of wheat-rust resistance in terms of input-savings.

Our findings show that the use of resistant wheat cultivars reduces the fungicide application (% of farms applying fungicide) and intensity (frequency of applications of fungicide). Specifically, we observed a reduction of 12.4% in application and 0.117 in intensity. Extending our analysis, we demonstrate that the input-saving effect of cultivar resistance can lead to an average cost saving of AU$7.98 per hectare across all production zones.

A significant reduction in reliance on fungicides also has the potential to promote sustainable disease management, especially in low-input cropping systems. However, such benefits can only be fully realized if significant effort is put into identifying effective incentives for the adoption and uptake of resistance deployment strategies to increase resistance durability.