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Rooting in Podocarpus falcatus (Thunb.)
Mirb. (syn. P. gracilior Pilg.) was studied using branch cuttings
and whole seedlings harvested from 3-month-old, 2-yearold, 4-year-old and
8-year-old stockplants. The study was conducted in two separate propagators
(two blocks) in which six different IBA treatments, viz. 0µg, 20µg,
40µg, 80µg, 160µg or 320µg IBA/cutting were administered to each of the 50–60
cuttings per treatment. The study found that cuttings from 3-month-old and
2-year-old stockplants responded well to IBA dosages between 20µg and 80µg/cutting,
but were inhibited at higher concentrations. Treatments higher than 40µg/cutting
significantly (P < 0.01) inhibited rooting in cuttings derived from the
4-year-old and 8-yearold stockplants. Rooting was significantly (P < 0.01)
better in cuttings derived from 3-month-old and 2-year-old stockplants than
from 4-year-old and 8-year-old stockplants. Indolebutyric acid significantly
(P < 0.01) shortened the time taken for 50% rooting-response in cuttings
derived from 3-month-old and 2-year-old stockplants. Notwithstanding the
poor rooting response, cuttings derived from 4-year-old and 8-year-old stockplants
produced far more roots per cutting than those from 3-month-old and 2-year-old
stockplants. Stecklings (plants derived from rooted cuttings) grew significantly
(P < 0.01) faster than seedlings, but plagiotropism in theformer remained
a persistent problem.

South African Journal of Botany 2002, 69(2): 170–175