VIRUSES IN THE FAMILY LUTEOVIRIDAE, COLLECTIVELY REFERRED TO HEREIN AS LUTEOVIRIDS, CAUSE ECONOMICALLY IMPORTANT DISEASES IN STAPLE FOOD AND OTHER CROPS. LUTEOVIRIDS ARE TRANSMITTED BY SPECIFIC SPECIES OF PHLOEM-FEEDING APHID VECTORS IN A CIRCULATIVE MANNER THAT INVOLVES THE MOVEMENT OF VIRUSES ACROSS AND WITHIN SPECIFIC INSECT TISSUES. LUTEOVIRIDS SHARE SEVERAL COMMON BIOLOGICAL TRAITS WITH OTHER PLANT-INFECTING CIRCULATIVE VIRUSES AS WELL AS ARTHROPOD-BORNE VIRUSES OF ANIMALS E.G., TISSUE TROPISMS IN HOSTS AND VECTORS AND CIRCULATIVE TRANSMISSION BY A LIMITED NUMBER OF VECTOR SPECIES. WE HAVE A BASIC UNDERSTANDING OF WHICH VIRUS PROTEINS ARE REQUIRED FOR TRANSMISSION, BUT THE DETAILS OF HOW THEY INTERACT WITH EACH OTHER AND WITH APHID PROTEINS TO FACILITATE TRANSMISSION ARE LACKING. DECIPHERING THESE DETAILS IS ESSENTIAL FOR THE DEVELOPMENT OF NOVEL STRATEGIES TO BLOCK VIRUS TRANSMISSION AND MANAGE VIRAL EPIDEMICS. THIS PROJECT FOCUSES ON UNDERSTANDING THE MOLECULAR DETAILS OF LUTEOVIRID TRANSMISSION BY APHIDS AND DEVELOPMENT OF A NEW TOOL TO BLOCK VIRUS TRANSMISSION.