The Economic Impact of Rice Blast Alleviation in the Mid‐South of the United States

The rice blast fungus, Magnaporthe oryzae, causes extensive damage to rice production globally, which often results in costly fungicide applications and yield losses. These inefficiencies harm farmers via increased costs in production and subsequently drive up food prices for consumers, which can, in turn, give rise to food insecurity in low-income countries. Moreover, there are blast-resistant rice varieties commercially available in the United States; however, breeding for resistance remains problematic because the fungus continuously evolves. In 2013, scientists at Kansas State University identified a blast- resistant gene in a wild rice variety that could be cisgenically transferred into currently cultivated, high- yielding varieties. Due to regulatory protocols on Genetically Modified Organisms in other countries, this technology is not been commercially available to producers. Consequently, the environmental and financial costs of fungicide applications and subsequent yield losses from the rice blast disease, remain high in the United States and other countries. Correspondingly, the aim of this study is to estimate the increased costs for three different rice blast scenarios in the Mid-South of the United States between 2002 and 2014. In the first scenario, we quantified the costs of two preventive fungicide applications to all hectares sown to blast-susceptible varieties; in the second, we quantified the costs of two mitigating fungicide applications on one blast outbreak area that was simulated based on historical outbreaks; and in the third, we quantified the costs of two mitigating fungicide applications on a simulated outbreak with additional yield loss caused by the fungus. The total financial costs of the rice blast disease for all years in each of the three scenarios were $265,691,269, $117,507,463, and $775,071,706 respectively. Overall, these findings necessitate: (1) more research on cisgenic breeding for blast resistance, (2) more robust policy negotiations, and (3) wide-spread adoption by farmers.