Susceptibility of Solanum phureja (Juz. et Buk.) to potato yellow vein virus

Sixty two virus-free accessions of Solanum phureja from the Colombian
central collection of this tuber (Bogotá-Soacha) were
tested for their susceptibility to infection with Potato yellow
vein virus (PYVV). Under greenhouse conditions, the plants
were inoculated with PYVV using viruliferous Trialeurodes
vaporariorum (Westwood) whiteflies, and monitored for three
months (the tuber formation period of S. phureja) for symptoms
of infection and virus capsid protein (CP) production, by means
of a reverse transcription-polymerase chain reaction (RT-PCR)
assay. Symptoms of PYVV infection, consisting in the chlorotic
flecking of leaflets, followed by complete vein yellowing, were
noted in 38 accessions whose RNA extracts generated correctsized
CP amplicons in RT-PCR assays. Thirteen of the remaining
accessions were found to be latently infected with the virus
through positive RT-PCR assays. Twelve accessions were free
of virus infection as judged by the absence of symptoms and
negative RT-PCR assay results over two cycles of tuber setting
and germination. These accessions may possess field resistance
to PYVV. This work is the first one to detect and define the levels
of susceptibility of Colombian S. phureja accessions to PYVV
infection, and to identify the potential existence of resistance
to this deleterious Andean potato virus