Increased Cytokinin-9-Glucosylation in Roots of Susceptible Solanum tuberosum Cultivar Infected by Potato Virus YNTN. Marina Dermastia. The National Institute of Biology, Karlovska 19, 61000 Ljubljana, Slovenia. Maja Ravnikar, and Maja Kovac The National Institute of Biology, Karlovska 19, 61000 Ljubljana, Slovenia. MPMI 8:327-330. Accepted 28 November 1994. Copyright 1995 The American Phytopathological Society.

Infection with potato virus YNTN (PVYNTN) changed root cytokinin metabolism in infected potato plants of the very susceptible cultivar Igor. There was a trend for a shift in concentrations of biologically active cytokinin free bases and ribosides toward the inactive 9-glucosides after primary infection. This change was even more marked after secondary infection and not observed in PVYNTN-resistant cultivar Sante.