The groundnut rosette virus is transmitted by aphids. Aphids are small insects that feed on the sap of plants. When they feed on a plant infected with the groundnut rosette virus, the virus can be transmitted to healthy plants through their mouthparts. Aphids can transmit the virus in a persistent manner, which means that the virus can remain in their bodies and be transmitted to other plants for a long period of time. This makes aphids a major vector for the transmission of groundnut rosette virus.