© 1987 Heron Publishing—Victoria, Canada
The physiological basis for loss of rootability with age in avocado seedlings
M. Raviv (1, 2), O. Reuveni (1) and E. E. Goldschmidt (3)
1. Department of Subtropical Horticulture, Agricultural Research Organization, The Volcani Center, Bet-Dagan, Israel / 2. Department of Floriculture, Agricultural Research Organization, Newe-Ya’ar, P.O. Haifa 31999, Israel / 3. Department of Horticulture, Faculty of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel / Received April 22, 1986
Summary
Rooting ability of cuttings from avocado (Persea americana Mill.) seedlings declined during the first 12 months of development. Cuttings from one-year-old seedlings rooted at a similar
rate to cuttings prepared from mature plants. The amount of gibberellin-like substances in the leaves decreased during this
time whereas abscisic acid content increased. Application of GA to avocado seedlings induced shoot elongation but failed to
maintain the initial, high rooting ability. Treatments with ABA and AM0 1618 had no effect on either rooting or elongation.
During the development of roots, the endogenous Avocado Rooting Promoter (ARP) accumulated at a faster rate in juvenile cuttings
than in mature cuttings.
