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

Kinetin & Kinetin Analogues as Substrates & Inhibitors of Xanthine Oxidase

“…The discovery of the stimulation of cell division in plant tissues by trace amounts of kinetin, 6-(2-furfuryl) aminopurine (11), has resulted in a number of investigations concerned with the effects of this and related compounds on a variety of plant and animal systems (4,5,7,9,10,12,13). One system, developed for study of the in situ effect of agents upon the maintenance of normal organization of cells in differentiated tissues, uses exposed tissues of planaria, a primitive invertebrate (7).…”

Cotyledon Expansion as a Bioassay for Cytokinins

“…In the subsequent decade, as various other activities tof cytokinins b,ecame evident, numerous other types of stimulations have been employed in bioassays. These include cytokinin stimulations of Lemna frond growth (2), of seed germination (11), of leaf enlargement (4), or the cytokinin deferral of leaf senescence (9 strongly stimulated by gibberellic acid; a comparison of benzyladenine and gibberellin concentration responses is shown in Fig. 2 Fig.…”

Stimulation of Lettuce Seed Germination by 6-(Substituted) Purines

“…Presoaking several varieties of seed, especially lettuce, in various 6-(substituted) amino-and thiopurine solutions has been found to increase their rate of germination (3,5,6). Recently it was also reported that these purine derivatives are synergistic with gibberellin in inducing these biological responses whereas gibberellin alone was only moderately active in stimulating germination of Early Curled Simpson lettuce seed (7,8).…”

“…Recently it was also reported that these purine derivatives are synergistic with gibberellin in inducing these biological responses whereas gibberellin alone was only moderately active in stimulating germination of Early Curled Simpson lettuce seed (7,8). The mode of biochemical action of these purine derivatives and gibberellin (2) in affecting the rate of germination is as yet unknown, although it has been observed that seed activation by white light is augmented by pretreatment of the seed with various 6-(substituted)purine solutions (6). Recently Miller (4) demonstrated that maximal purine-activation of Grand Rapids lettuce seed germination is somewhat dependent on the presence of light.…”