MICROPROPAGATION OF PACIFIC DOGWOOD

Idaho's population of Pacific dogwood (Cornus nuttallii Audubon) has d eclined. Propagation of disease-resistant clones would be useful to ho rticulturists and conservation biologists. In vitro-derived microshoot s, incubated for 1 month on woody plant medium supplemented with 6.04 mM calcium gluconate and 4.44 mu M benzyladenine, produced an average of 3.1 axillary microshoots per explant. Up to 62% of the elongated mi croshoots had rooted ex vitro 5 weeks following a 4.5% IBA talc dip. P lantlets resumed shoot growth within 2 months of acclimatization, and 70% survived after 1 year. This protocol is more rapid and efficient t han propagation by layering or rooting the difficult-to-root stem cutt ings of this species. Chemical names used: 2,3,4,5,6-pentahydroxy-capr oic acid (calcium gluconate), benzyladenine (BA), 3-indolebutyric acid (IBA).