ARS | Publication request: Resistance to the Poerovirus Cereal Yellow Dwarf Virus in Wheat: A Two-component system

Submitted to: Plant Animal and Microbe Genomes Conference
Publication Type: Abstract Only
Publication Acceptance Date: December 1, 2007
Publication Date: January 12, 2008
Citation: Anderson, J.M., Wiangjun, H. 2008. Resistance to the Poerovirus Cereal Yellow Dwarf Virus in Wheat: A Two-component system. Plant Animal and Microbe Genomes Conference. W379.

Technical Abstract: The mechanism of resistance to Cereal yellow dwarf virus (CYDV), introgressed into wheat from Thinopyrum intermedium, is unclear as previous data demonstrated that it was not due to a block in virus replication. Through cellular analysis we have examined the movement of CYDV within inoculated and uninoculated leaves of resistant and susceptible wheat lines. In the vascular system of the resistant wheat line P29, CYDV localized only to a few phloem cells and its systemic movement through the sieve tube was inhibited. Comparisons between the percentage of infected non-phloem cells of the resistant line P29 and the susceptible wheat line Abe also showed that this resistance interfered with phloem feeding of the insect vector. The inhibition of phloem feeding results in a reduced number of CYDV-infected phloem cells. Once inside the sieve tube members virus movement through the sieve tubes is blocked indicating that movement within the translocation stream of macromolecules such as viruses can be regulated downstream of the sieve element/companion cell complex.. Collectively this resistance decreases the number of inoculation foci and confines the virus to a highly localized infection, thereby, leading to a reduction in the disease spreading to neighboring plants. This study demonstrates that Th. intermedium-derived resistance is a two-component system consisting of resistance to the aphid vector and pathogenic virus.