Propagation of Scabiosa hymettia (Boiss. & Spruner) by stem cuttings

Abstract

Scabiosa hymettia Boiss. & Spruner (syn. Lomelosia hymettia, fam. Dipsacaceae) is an endemic xerophyte of central and southern Greece, and of the northern Aegean region. It is a small shrub of the macchia zone, very attractive from May to mid-July when it bears blue-purple flowers on elongated flower peduncles. In the present study its vegetative propagation by stem cuttings was investigated, in order to introduce the species as an ornamental plant in urban and suburban areas and historical Mediterranean landscapes. Cuttings derived from the apical part of shoots, 15 cm long, bearing two to four lateral shoots, were collected from a wild population at mount Parnitha (prefecture of Attiki, Greece), in spring (March), summer (August), autumn (October) and winter (January) for two consecutive years. The base of the cuttings was immersed either in powder indole-3-butyric acid (IBA) for herbaceous/softwood or for hardwood cuttings, or in IBA ethanol-water (1:1, v/v) solutions, at four different concentrations: 0 (control), 1000, 2000 and 3000 mg L(‑1), for two dipping times, 1 or 5 min, and were put for rooting on a mix of 1 peat:1 perlite (v/v) in a mist system for two weeks and then on a heated-glasshouse bench for further six weeks. Almost all cuttings (92.5-100%) collected in autumn and winter rooted when treated with powder IBA for hardwood cuttings, or with 1000 mg L(‑1) IBA ethanol-water solution for 1 min, while the controls rooted at 45-65%. In spring and particularly in summer, cuttings rooted at lower rates compared to autumn and winter. Best response in spring was achieved with the use of powder IBA for hardwood cuttings (50% rooting), or with 5 min dipping in IBA solutions (50-67.5% rooting). In summer highest rooting was induced either with powder IBA for hardwood cuttings (45.0%) or with 1000 mg L(‑1) IBA for 1 min dipping time (37.5%).