Unveiling wheat rust epidemics: A long-term surveillance study in Ethiopia's North Western Amhara region

Wheat is one of the most significant food security crops in Ethiopia. However, the production and productivity of wheat is far below its potential due to many challenges. Wheat disease epidemics, typified by wheat rusts, are among the most important challenges, causing large-scale production losses that put farmers’ income and food security at risk. We analysed and presented the long-term and comprehensive wheat rust surveillance results to better understand the past rust disease occurrences, ultimately contributing to future wheat production and rust control strategies. A total of 1140 wheat fields have been surveyed from 2009 to 2021 throughout four administrative zones of the North Western Amhara region. We identified spatial and temporal trends in the distribution and status of wheat stem rust (Sr), yellow rust (Yr) and leaf rust (Lr) using a combination of different statistical tools and data-analysis methods. The results of the study indicated that 52.5%, 11.3% and 3.4% of the wheat fields were infected with yellow, stem and leaf rust, respectively. Even so, the distribution and intensity of wheat rust disease vary across locations, elevations and cultivated varieties. The associations between altitude and disease prevalence show a linear correlation. We also identified hotspots of yellow and stem rust, which will be used by the country's wheat rust disease early warning system. In order to reverse low varietal diversification in the farmer's field, it is necessary to work with all stakeholders involved in the wheat production sector in a better synergy.