Regrowth Response of London Plane Injected with Dikegulac at Different Stages of Tree Development

Abstract

Three-year-old London plane (Platanus acerfolia) trees pruned at 5 different stages of plant development were injected with dikegulac [2,3:4,6-bis-0)1-methylethylidene)- 0(-L-xylo-2-hexulorfuranosonic acid)]. At the end of the growing season, sprout length, number of new sprouts, and phytotoxicity were determined. Maximum growth reduction with minimum foliar damage was obtained on injected trees pruned at half-leaf development stage. Even though greater growth reduction was obtained on injected trees pruned at fullleaf development stage, the phytotoxicity was unacceptable.