Determining the rooting characteristics of cuttings from different genotypes of two boxwood species naturally occurring in Türkiye

Abstract

Boxwood species are important because they are widely used as ornamental plants and for various other purposes in Türkiye and worldwide. In this study, cuttings of 189 B. sempervirens genotypes and 17 B. balearica genotypes collected from natural boxwood populations in Türkiye were propagated. This study aimed to examine the propagation potential of two wild-collected boxwood species using semi-hardwood cuttings. Different genotypes significantly influenced the success of cutting propagation and the rooting characteristics of the cuttings. In 63% (120) of the B. sempervirens genotypes, the rooting rate was 50% or higher, whereas in 34% (65) of the genotypes, cutting rooting was less than 50%. No rooting was observed in four genotypes (3%). In B. balearica, 82% of the genotypes (14) showed rooting in 50% or more of the cuttings, while 18% of the genotypes (3) showed rooting in less than 50% of the cuttings. The root length, root width, root number, shoot length, leaf number, callus induction rate, and rooting rate of B. sempervirens ranged from 42.3–253.0 mm, 35.2–210.0 mm, 3.5–30.0, 15.0–60.0 mm, and 2.5–12.0 leaves, respectively. The callus induction rate and rooting rate ranged from 1% to 83% and from 5% to 99%, respectively. The corresponding values in B. balearica ranged from 39.0–116.9 mm, 33.8–136.0 mm, 3.8–21.3, 2.0–42.1 mm, 4.0–8.2 leaves, 2–45%, and 20–98%, respectively. While the average rooting rate was 54.9% in B. sempervirens, it was 71.4% in B. balearica. The root quality of rooted cuttings of both species was assessed on a scale of 1 to 5 points and depended on their genotype; the average root quality was 4 points.

Keywords: boxwood; Buxus sempervirens; Buxus balearica; cuttings; rooting characteristics; natural plants