Indolebutyric acid on boxwood propagation by stem cuttings

Abstract

Buxus sempervirens L., popularly known as boxwood, is a woody shrub widely used in gardening and landscaping. One of the most important factors for B. sempervirens commercial production is its propagation. The objective of this study was to evaluate the effect of indolebutyric acid (IBA) concentrations on the adventitious rooting of semihardwood stem cuttings of the species. Branches with new shoots were collected from stock plants with approximately 17 years of growth. Stem cuttings of six centimeters in length with two leaves in the upper region were made with a straight cut at the apex and a bevel cut at the base. Cuttings bases were immersed for 10 seconds in hydroalcoholic solutions (50% v v-1) with IBA at 0, 1500, 3,000 or 6,000 mg L-1. The cuttings were evaluated at 64 and 116 days after planting. Rooting, mortality, callus formation and sprouting percentages as well as root number and root length were measured. At 64 days, no significant percentage of rooting was observed in B. sempervirens stem cuttings and sprouting and callus formation were not significantly affected by the treatments. Keeping the cuttings in the greenhouse for 116 days led to rooting rates up to a 97.5%, with no statistical difference among treatments. Root lengths and root numbers did not differ as a function of treatments. The required period for B. sempervirens stem cuttings rooting is around 116 days; IBA application does not affect rooting, survival or sprouting of B. sempervirens stem cuttings.

Keywords

• Auxin
• Buxus sempervirens L.
• rooting
• vegetative propagation.