In Japan, a recent outbreak of the plum pox virus (PPV)-D strain in Japanese apricot has caused serious plant quarantine concerns. The vertical transmission of the virus from infected Japanese apricot trees to seedlings was investigated in one major cultivar (‘Nanko’) and two minor cultivars (‘Baigo’ and ‘Komukai’), by immunochromatographic assays using young leaves from 2-month-old seedlings. No PPV-positive seedlings were found among 328 ‘Nanko’, 61 ‘Baigo’, and 8 ‘Komukai’ seedlings. The results indicated that the PPV-D strain in Japan is not vertically transmitted from infected ‘Nanko’ plants to seedlings. Further experiments are needed to test other cultivars, including ‘Baigo’ and ‘Komukai’.