Summary
The research was carried out by the University of Singapore and the Université de Montpellier in France. The research was published in the journal Nature. The researchers hope to use the information to improve the health of coffee plants. They hope to also improve the quality of coffee. In 2012 and 2014, an outbreak of coffee leaf rust caused about US$1.36 billion in damages. According to the U.S. Agency for International Development, the number of people affected is expected to rise. The U.N. estimates the number will rise to 2.5 million by 2018. Arabica plants have low genetic diversity, which makes them susceptible to pests and diseases. The loss of leaves lowers the quality and quantity of the plants' berries harvested for coffee. To prevent a potentially disastrous wipeout of Arabica plants, the researchers mapped out the genomic origins and history of the plant. This is the first time in history that the same species of plant has been found to be able to grow in the same place. The discovery was made by studying the roots of the coffee plant. It is the second time in the history of the world that this has been discovered. Using the plants' genome information, the researchers were able to map the different types of resistance. Knowing the existence of these genes increases the likelihood that these genetic sequences can indeed defend against leaf rust. Knowing these genes could allow breeders to select for them in new coffee varieties. The first Arabica plants were created by cross-pollination of Robusta and C. eugenioides. This means that the species are still highly similar genetically. This suggests that for future breeding programs to ensure that Arabica. plants have disease resistance, breeders can consider using other related coffee species. Using Arabica plants alone to breed for the resistance trait is problematic. Even the wild varieties of Arabica have very low genetic diversity. The highly detailed genomic sequences could be used to identify useful traits. These include resilience to drought, better crop yield and more aromatic coffee beans.