Influence of temperature and photoperiod on cytokinin pools in the potato, Solanum tuberosum L.

Abstract Using the cucumber cotyledon bioassay, total cytokinin activity in Katahdin potato plants grown under inducing conditions (26° day and 12° night with an 8-h photoperiod) was found to be significantly higher than that of plants grown under non-inducing conditions (30° day and night with a 16-h photoperiod). Highest cytokinin activity was observed in induced, above-ground tissue after 4 days. In induced, below-ground tissue, highest cytokinin activity was observed after 6 days, with tuber initiation after 8 to 10 days.