International Crops Research Institute for the Semi-Arid Tropics
Abstract
Groundnut rosette is a major disease of groundnut (Arachis hypogaea L.) endemic to sub-Saharan Africa. The disease is restricted to the African continent and its offshore islands. It is responsible for annual groundnut yield loss worth over US$150 million. A complex of three agents is involved in rosette disease etiology: Groundnut rosette assistor virus (GRAV; Family, Luteoviridae), Groundnut rosette virus (GRV; Genus, Umbravirus) and a Satellite-RNA (SatRNA) associated with GRV. The disease is spread in nature by the aphid vector, Aphis craccivora Koch, and occurs in two predominant symptom forms, chlorotic rosette and green rosette. Past research has revealed that SatRNA is responsible for rosette disease symptoms. GRAV or GRV on their own cause mild mottle symptoms. GRV functions as helper for SatRNA replication, whereas GRAV functions as helper virus in vector transmission of GRV and SatRNA. Through over 30 years research experience on this disease, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) and its partners have made significant contributions towards the understanding of rosette disease etiology, molecular characterization, virus-vector interactions and development of serological (enzyme-linked immunosorbent assay) and nucleic acid (dot-blot hybridization and reverse transcription-polymerase chain reaction) based diagnostic assays. This knowledge has provided basis for development and utilization of groundnut cultivars with resistance to the groundnut rosette disease and impacted the lives of thousands of farmers in sub-Saharan Africa. This information bulletin provides an overview of the groundnut rosette disease, properties of the etiological agents, protocols for their detection, information on screening groundnut germplasm for resistance to the disease and resistant sources, and various management option
