Alliance from Science
BY JOSEPH OPOKU GAKPO
Work has begun to possibly develop CRISPR cassava varieties that are resistant to the deadly cassava mosaic disease (CMD), after an international team of research scientists managed to identify a gene responsible for the resistance.
The team, led by Wilhelm Gruissem, a professor of Plant Biotechnology at the Swiss Federal Institute of Technology in Zürich (ETH Zurich), finally pinned down the gene responsible for what is known as the cassava mosaic disease 2 (CMD2) resistance in some cassava cultivars. Working with several resistant and susceptible West African cassava cultivars, the team used elaborate and time-consuming genome analyses to identify the gene responsible for a specific resistance to cassava mosaic virus. The research team included scientists from National Crops Resources Research Institute in Uganda, Donald Danforth Plant Science Center in St. Louis, Missouri, and the University of California, Los Angeles.
The gene that has been identified now serves as a genetic marker for breeders, indicating whether the resistance is present in their plants, and can be used in guiding development of resistant varieties. In an interview with the Alliance for Science, Gruissem explained that about 30 years ago, farmers in West Africa found cassava plants in the fields damaged by CMD that looked healthy, indicating they were resistant. Although the trait can be introduced in other cassava cultivars using conventional plant breeding processes, such efforts are usually time consuming and the improved varieties do have undesired traits as well.