Coffee leaf rust (Hemileia vastatrix) – roya in spanish – is a fungus which attacks Coffea arabica originally from Ethiopia but now a major economic export of central american countries especially Colombia. Recent outbreaks of roya have been estimated to have cost several hundred million USD dollars . Control of roya is possible with fungicide however a better method is to cultivate resistant varieties. Roya resistant varieties exist, however they have less appealing taste characteristics. In order to minimise impact on taste it would be ideal to cross the minimum set of resistance genes necessary to protect the original arabica coffee crop. The recent identification of arabica coffee plant proteins responsible for roya resistance should make this task simpler .
A proteomic comparison of arabica coffee plants infected with a strain of roya that causes infection and a strain that is unable to infect has allowed the identification of coffee plant proteins that mediate roya resistance . Antibodies have been developed against these roya resistance proteins and should facilitate the selection of resistant arabica cultivars with ideally the minimal impact on coffee taste.
Upon confirmation of these putative resistance markers by testing for them in a wider range of resistant coffee plants they can be used in marker assisted breeding programs which will hopefully speedily generate new commercially viable and roya resistant arabica coffee plant strains which will help maintain the economy of rural central america.
- Avelino, Jacques, Marco Cristancho, Selena Georgiou, Pablo Imbach, Lorena Aguilar, Gustavo Bornemann, Peter Läderach, Francisco Anzueto, Allan J. Hruska, and Carmen Morales. ‘The Coffee Rust Crises in Colombia and Central America (2008–2013): Impacts, Plausible Causes and Proposed Solutions’. Food Security 7, no. 2 (April 2015): 303–21. doi:10.1007/s12571-015-0446-9.
- Guerra-Guimarães, Leonor, Rita Tenente, Carla Pinheiro, Inês Chaves, Maria do Céu Silva, Fernando M. H. Cardoso, Sébastien Planchon, Danielle R. Barros, Jenny Renaut, and Cândido P. Ricardo. ‘Proteomic Analysis of Apoplastic Fluid of Coffea Arabica Leaves Highlights Novel Biomarkers for Resistance against Hemileia Vastatrix’. Frontiers in Plant Science 6 (30 June 2015). doi:10.3389/fpls.2015.00478.