Effect of Light Intensity during Stenting Propagation on Rooting and Subsequent Growth of Two Rose Cultivars

Abstract

This study was conducted to investigate the effect of light intensity during a winter season on rooting and subsequent growth of stenting-propagated domestic cut rose (Rosa hybrida Hort.) ‘Pink Aurora’ and ‘Yellow King’ in an effort to develop an efficient stenting propagation method for rose cultivars. To facilitate graft joining, both base of scion and top of rootstock, removed leaves, were cut together at a 45˚ angle. Single node scions, each with a five-leaflet leaf, were grafted on Rosa indica ‘Major’ as the rootstock. A scion-rootstock union was stuck in a rockwool cube (5 cm × 5 cm× 5 cm, Grodan, Denmark) and was placed in a graft-take chamber for five days before being moved to a misted greenhouse bench. Plants were grown under 650 (0%), 228 (35%), or 125 (55%) μmol·m^-2·s^-1 of the incident sunlight. Rooting and growth were affected by the light intensity and cultivar. In both cultivars, root growth was accelerated and percent rooting increased under higher light intensities. No shading generally showed the highest percent rooting, shoot length, shoot weight, length of longest root, and root weight. Chlorophyll content was not significantly affected by the light intensity. The greatest rooting and subsequent growth of stenting-propagated plants were found in the no shading. The results suggested that shading was not necessary for the stenting propagation of domestic cut rose cultivars during a winter season.