Cucumber mosaic virus has plant species-specific effects on host-vector interactions
T. TUNGADI (1), A. Murphy (1), A. Pate (1), J. Iqbal (1), J. Carr (1) (1) Department of Plant Sciences. University of Cambridge, United Kingdom

Cucumber mosaic virus (CMV) has a broad host range and is non-persistently transmitted by aphids. In tobacco and Arabidopsis thaliana, CMV infection has plant species-specific effects on host-aphid interactions. CMV infection of Arabidopsis deters aphids (Myzus persicae) from prolonged feeding, partly due to the increased production of the aphid deterrent glucosinolate, 4-methoxy-indol3yl-methylglucosinolate. Contrastingly, on CMV-infected tobacco, aphids showed increased sustained phloem ingestion. We hypothesize that non-persistently transmitted viruses induce two types of change in host-vector interactions. In a ‘Type 1’ interaction (exemplified on CMV-infected Arabidopsis), infection induces feeding deterrence, leading to vector dispersal. In a ‘Type 2’ interaction (exemplified on CMV-infected tobacco), virus infection has a more positive effect on the aphids and this may facilitate recovery of the vector populations. CMV is a positive-sense RNA virus with three genomic segments that between them encode five proteins. In CMV-infected Arabidopsis, aphid deterrence comes from the interplay of three CMV proteins; protein 1a, 2a and 2b. In tobacco, roles of individual CMV proteins in shaping the host-aphid interaction are not yet known. On tobacco infected with a 2b deletion mutant from strain Fny, aphids survived less well and formed smaller colonies. However infection of tobacco with a 2b deletion mutant from the LS strain had no detrimental effect on the aphids. We used a combined approach of generating transgenic plants to express CMV protein and reassortant viruses from the Fny and LS-CMV strains, to map the CMV elicitors of aphid resistance on tobacco to RNAs 1 and 2.

Abstract Number: C16-2, P5-134
Session Type: Concurrent