An Agar-diffusion Technique Applied to the Study of Gibberellins in Tomato (Lycopersicon esculentumMill.) Plants

Effects of CCC on the Formation and Abortion of Flowers in the First Inflorescence of Tomato (Lycopersicon esculentum Mill.)

“…Jones and Phillips (1967) observed no reduction in the yield of diffusible gibberellins from apical buds of sunflower when CCC was applied as a soil drench only, but a marked reduction occurred when CCC was also supplied in the agar blocks on which the excised buds were stood. The effectiveness of the soil drench treatment for tomato was consistent with the view that, for this plant, the agar diffusion technique measured levels of gibberellins in the shoot tips at the time of their excision rather than gibberellins synthesized during the diffusion period (Abdul and Harris, 1977). Support for the hypothesis that effects of CCC on flowering in tomato were mediated, in part at least, by reduction in levels of endogenous gibberellins came from comparisons…”

“…Eurocross BB were grown in the glasshouse as described by Abdul and Harris (1977). A minimum temperature of 16 °C was maintained with ventilation given when the temperature exceeded 23 °C.…”

“…The procedures used for the diffusion, for the extraction of gibberellin-like substances from the agar blocks and for the bioassay of the extracts were as described by Abdul and Harris (1977). One hundred shoot tips were taken from plants in each treatment and were stood on agar blocks containing 0-01 M phosphate buffer (pH 5-8) for a period of 24 h. The aqueous residue recovered after vacuum distillation of the methanolic extract of the blocks was acidified to pH 2-5 before extraction with ethyl acetate.…”