LISIANTHUS GROWTH AND FLOWERING RESPONSES TO UNICONAZOLE

One and two foliar spray and single-drench applications of uniconazole were applied to Eustoma grandiflorum (Raf.) Shinn (lisianthus) 'Yodel Blue' to determine optimal concentrations for potted plant height control. A single uniconazole spray at 10.0 mg.liter-1 applied 2 weeks after pinching, two uniconazole applications at 5.0 mg.liter-1 applied 2 and 3 weeks after pinching, or a drench at 1.60 mg a.i. per pot applied 2 weeks after pinching gave equally good height control. At these concentrations, uniconazole was similiar in its effect on plant height to daminozide foliar sprays at 7500 and 2500 mg.liter-1 applied once and twice, respectively. Drenching with uniconazole at 1.60 mg a.i. per pot did not increase days to flower (DTF), whereas foliar spray applications did. Drenching did not reduce flower size, but increased flower number at time of harvest. Chemical names used: alpha-cyclopropyl-alpha-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono(2,2-dimethylhydrazide) (daminozide); (E)-(S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-ol (uniconazole).