Researchers Identify Plum Pox Virus Susceptibility Genes in Apricot

Plum pox virus (PPV), which causes Sharka disease, is one of the main limiting factors for apricot production. In apricot (Prunus armeniaca L.), the major PPV resistance locus (PPVres) has been mapped to the upper part of linkage group 1. Elena Zuriaga and her colleagues from Instituto Valenciano de Investigaciones Agrarias in Spain predicted that meprin and TRAF-C homology domain (MATHd)-containing genes as PPV resistance candidate genes.

The team characterized the global apricot transcriptome response to PPV-D infection and identified six PPVres locus genes, ParP-1, -2, -3, -4, -5 and -6, differentially expressed in resistant and susceptible cultivars. Two of these, ParP-3 and ParP-4, encoding MATHd proteins, were found to be downregulated in resistant cultivars.

ParP-3 and ParP-4, termed Prunus armeniaca PPVres MATHd-containing genes (ParPMC), are the only 2 genes having allelic variants linked to PPV resistance. Resistant cultivars carrying the ParPMC2 mutated allele showed lack of expression in both ParPMC2 and especially ParPMC1.

The results show that ParPMC1 and/or ParPMC2 as host susceptibility genes required for PPV infection and silencing these may confer PPV resistance trait.

For more information on the study, read the article in BMC Plant Biology.