A first approach for evaluation, breeding and promotion of native to Greece sage species for use as landscape plants

Following the current tendency for xeriscaping and considering the ecological, environmental, economic and aesthetic advantages of native plants, clones of native in Greece sage species were evaluated and interspecific crossings were performed.
Aim was to obtain hybrids with floricultural characteristics sought on the international market of ornamental herbs, such as compact plant shape, abundant and prolonged flowering, drought resistance, and ease of growth. Salvia fruticosa and S. officinalis were crossed with S. pomifera ssp. pomifera, S. ringens and S. tomentosa and each clone was used both as a pollen and seed parent for all crossings.
Crossability was observed only when S. officinalis and S. fruticosa were used as seed parent, apart from the cross S. tomentosa × S. fruticosa that succeeded with S. fruticosa as pollen parent too.
Hybrids with desirable characteristics were selected for further experimentation concerning substrate and fertilization and drought tolerance in a green roof. S. officinalis × S. ringens and S. officinalis × S. tomentosa developed a compact plant shape and the most lateral shoots.
All hybrids survived water stress better than S. fruticosa, especially those of S. ringens. Germination of all species was highest at 10-15°C, indifferent to photoperiod, however S. tomentosa and S. ringens in all germination trials showed very low germination ability (less than 20%) and the other three species had an unstable response. S. pomifera ssp. pomifera presented up to 45% germination in peat-perlite without any pre-treatment, while S. fruticosa and S. officinalis up to 85% in MS medium, after scarification.
Propagation by cuttings was highly successful (70-96%, average of four seasons) for all species and hybrids.
As regards micropropagation, shoot multiplication was favoured in MS medium with 0.4 mg L^‑1 BA and 0.01 mg L^‑1 NAA, and rooting in half-strength MS medium with 0.25-1.0 mg L^‑1 IBA, while plantlets acclimatized ex vitro at percentages higher than 80%. All species, except S. fruticosa, and four selected hybrids, S. fruticose × S. ringens, S. officinalis × S. ringens, S. officinalis × S. pomifera ssp. pomifera, S. officinalis × S. tomentosa, survived drought stress in an extensive green roof and proved suitable for xeriscaping.

VIII International Conference on Landscape and Urban Horticulture

M. Papafotiou, A.N. Martini, K.F. Bertsouklis, G. Vlachou, E. Kanellou, E.G. Stylias, A. Kalantzis, L. Tassoula, E. Dariotis

Salvia fruticosa, Salvia officinalis, Salvia pomifera, Salvia ringens, Salvia tomentosa, native Mediterranean ornamentals, xeriscaping

https://doi.org/10.17660/ActaHortic.2022.1345.48