Abstract
Oxytetracycline (OTC) suppressed leaf scald symptoms in plum following trunk injection. Tools required were a cordless drill, a 28/163cm drill bit, a hammer and J.J. Mauget's OTC capsules. Two injection schedules, one in late April or early May and the other in mid October, were selected for the best effect. Two capsules, each containing 0.16g of OTC in 4ml solution were injected into each tree each time and two capsules of carrier solution were injected in control trees. After the first, third, and fifth injection in April, 1984, May, 1985 and May, 1986, respectively, OTC caused 61.5-100%, 73.3-100%, and 76.9-100% symptoms suppression recorded in August, 1984, 1985, and 1986, respectively. In May, 1985, after the second injection was administered in October, 1984, treated trees showed much less twig dieback than control trees.
