Detectability and translocation of potato virus A in potato plants after artificial inoculation

Summary The tip leaflets of median leaves of plants of different ages of the very susceptible cv. Jara and the less susceptible cv. Krasava were dry inoculated with potato virus A (PVA). Movement of the virus was followed by using the A6 leaf test on different plant perts at intervals after inoculation. The technique was not very reliable but the results showed that in cv. Jara the rate of movement of virus within the plants and into the tubers was greater and less dependent on their age than in the less susceptible cv. Krasava. In cv. Jara. PVA reached the tubers with 6–7 days from inoculation but in cv. Krasava not until after 21 days and not at all if the plants were more than 6 weeks old when inoculated.