Branching and rooting of six ornamentals following treatment with dikegulac-sodium and indolebutyric acid

Cuttings of Forsythia intermedia, Hedera I helix, Ilex attenuata 'Fosteri', Juniperus conferta, Lagerstroemia indica and Photinia x fraseri were either sprayed or soaked at 0, 1, 5, 10, 20, or 40 ml/1 of dikegulac-sodium (DKS) and for each method of application, half the cuttings were dusted with indolebutyric acid.

For cuttings of Forsythia intermedia, DKS at 20 ml/l was most effective on branching. DKS in excess of 5 ml/l reduced root quality grade and root dry weight, but DKS was not detrimental to rooting of this species.. The spray method and IBA were favorable to root development.

For cuttings of Hedera helix, DKS was more effective when sprayed at concentrations of 1, 5, or 10 ml/1 and when cuttings were dusted with IBA.

DKS had no effect on branching of cuttings of Ilex attenuata 'Fosteri'. When used as a spray at 1 to 20 ml/l, it was not very detrimental to rooting. IBA treatment produced a higher rooting percentage.

For cuttings of Juniperus conferta, DKS was most effective at 1 ml/l. The spraying method and IBA treatment were most favorable to root development.

DKS at 10 ml/l as a soak treatment was most effective on cuttings of Lagerstroemia indica. IBA treatment was favorable for both branching and rooting.

iv The average rooting percentage of Photinia x fraseri was 14.2. Data taken from this species were not analyzed or discussed. Further investigation of treatment effects on photinia over longer time periods may be warranted.