among rooting substrate, phenological stage of cuttings and auxin
concentration on the rooting of Cotinus obovatus .
C.;Arnold, M. A.
Department of Horticultural Sciences, Texas
A&M University, Mail Stop 2133, College Station, TX 77843-2133, USA.
|A study was
conducted to determine the effects of substrate, phenological stage of
cutting, and auxin concentration on the rooting of the ornamental Texas
smoke tree (C. obovatus ). Cuttings from new lush growing tips
(softwood), partially matured tissues (semi-mature wood) and mature
woody fully lignified cuttings from the previous season's growth (mature
wood) were treated with either 0, 5000, 10000 or 15000 mg potassium
salt of indole-butyric acid (K-IBA)/litre and placed in either 50%
peat:50% perlite or 100% perlite rooting substrates. Cuttings were
placed under an intermittent mist system in a greenhouse for 8 weeks.
Softwood cuttings rooted in both substrates, but the 50% peat:50%
perlite substrate produced better quality rooted cuttings. Softwood
cuttings peaked at 8000 to 10000 mg K-IBA/litre. Semi-mature wood and
previous season's growth cuttings rooted only in the 100% perlite
substrate. In 100% perlite substrate, the optimum concentration for
semi-mature wood cuttings was approx equal to 12000 mg K-IBA/litre,
while mature wood rooting was maximized at 15000 mg K-IBA/litre or more. .