MICROPROPAGATION OF CUPRESSUS-SEMPERVIRENS L. AND CHAMAECYPARIS-LAWSONIANA (A. MURR.) PAR

Shoots from 18-month-old seedlings of Cupressus sempervirens and Chama ecyparis lawsoniana were established in vitro on modified MURASHIGE an d SKOOG medium. Proliferation of axillary shoots occurred without addi tion of benzyladenine, although a significant increase in numbers of s hoots resulted on addition of 0.001 mg.l(-1) to 1.0 mg.l(-1) benzylade nine. Following conditioning on a growth regulator-free medium for 28 days, 95% of C. sempervirens shoots rooted on 1/2 strength medium cont aining 1% sucrose and 0.5 mg.l(-1) indole butyric acid. Similar levels of rooting were recorded with Chamaecyparis lawsoniana on the same me dium containing 1 mg.l(-1) indole butyric acid. C. sempervirens shoots were also rooted in non-sterile conditions. Over 80% of rooted shoots of C. sempervirens were weaned into glasshouse conditions. The signif icance of these results in relation to propagation of cypress clones r esistant to Seiridium canker is discussed.