Distribution of coat protein and nucleic acid of Plum pox virus (PPV) in seedlings of peach rootstock GF305 and apricot cv. Real Fino

Abstract

In this work, the in-plant distribution of Plum pox virus (PPV) in seedlings of peach rootstock GF305 and apricot cv. Real Fino was studied. Symptom severity and the optical density with the ELISA-DASI test were determined in the leaves. Occurrence of the virus (coat protein and nucleic acid) in the stems and petioles was analyzed by tissue printing of sections. The in-plant distribution of PPV was very irregular in both species, even in severely infected plants. It was also more erratic in seedlings showing an irregular distribution of symptoms, mainly in apricot. A correlation between occurrence of symptoms and localization of coat protein and nucleic acid was also observed. The irregular distribution of the virus, as regards both coat protein and nucleic acid, has negative implications for PPV resistance evaluation, since it renders virus detection and secure inoculation more difficult.