Stimulation of seed germination by 6-(substituted)thiopurines

Effect of 6-(Substituted)Thio- and Amino-Purines on Germination of Lettuce Seed.

“…These latter results were interrelated to the red light effect previously observed as a requirement for lettuce seed germination (2). We have also observed such an effect with 6-(substituted)thiopurines (12).…”

External Factors Inducing Germination of Fern Spores

“…The three purine-cytokinins, kinetin, benzyladenine, and zeatin, also had no effect on dark-germination at any of several tested concentrations. Kinetin has been shown to promote the dark germination of lettuce seeds (Miller, 1956, Skinner et al, 1956Ikuma and Thimann, 1963;Leff, 1964), which are also strongly responsive to gibberellin. The effect of kinetin is an enlargement of the cotyledons rather than the usual elongation of the epicotyl, which is characteristic of gibberellin or red light-induced germination (Scheibe and Lang, 1965).…”

The Cytokinins

“…Early work, summarized by Strong (2), indicated that high activity was restricted to N6-substituted adenines. In general, other workers have confirmed these findings (35,37,42). However, the differing specificities of various tests have prevented full agreement.…”