In vitro break of dormancy of axillary buds from woody species (Persea indica and Arbutus unedo) by sectioning with a laser beam

The effect of laser cut of explants on the break of dormancy of axillary bu ds and the development of micropropagated Persea indica and Arbutus unedo n odal segments was investigated. A continuous CO2 wave laser was used. A reg ular cut was obtained with a laser power of 75 W and a corresponding cuttin g speed of 0.01 m s(-1). Using these parameters, the surfaces of the segmen ts were cut consistently with little or no disruption of the neighboring ce lls and tissues, in contrast to the irregular cut made with a surgical blad e, especially at the level of vascular vessels. For both species studied, w hen the sectioning was performed in November or December, the laser cut pro moted break of dormancy of axillary buds and a faster growth of the resulti ng shoots. When sectioning was carried out in February, the laser cut had l ittle or no effect on axillary bud development. (C) 2001 Elsevier Science I reland Ltd. All rights reserved.