Effects of pre-treatments and temperature on seed viability and germination of Juniperus macrocarpa Sm.
The effects of collecting season, collection site, laboratory pre-treatments and temperatures on seed viability and germination of Juniperus macrocarpa were investigated. Ripe cones were collected in four Sardinian dune systems, in two seasons, from plant and soil. Warm (W) and cold (C) stratifications, two combinations of them (W+C, C+W), and no pre-treatment (0) were applied. Seeds were incubated in a range of constant (10-25°C) and an alternating (25/10°C) temperature regime. Seed viability was low (ca. 40%) and varied significantly according to the collecting season. Seed germination was also low (ca. 10%), the 0 and W were the most effective pre-treatments on stimulating germination. The best germination temperature, without any pre-treatment, was 15°C (ca. 20%). J. macrocarpa seeds are dormant and the achieved results suggested that the presence of secondary dormancy is induced by cold stratification. Spring appeared to be the best season for seed collecting, whereas autumn was the best for sowing. These results give new findings for restoration activities on this species.
Centro Conservazione Biodiversità (CCB), Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Viale Sant'Ignazio da Laconi, 13, 09123 Cagliari, Italy.
Maria Silvia
MS
Pinna
Centro Conservazione Biodiversità (CCB), Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Viale Sant'Ignazio da Laconi, 13, 09123 Cagliari, Italy; Seed Conservation Department, Royal Botanic Gardens, Kew, Wellcome Trust Millennium Building, Wakehurst Place, Ardingly RH17 6TN, West Sussex, United Kingdom. Electronic address: e.mattana@kew.org.
Efisio
E
Mattana
Centro Conservazione Biodiversità (CCB), Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Viale Sant'Ignazio da Laconi, 13, 09123 Cagliari, Italy; Departamento de Botánica. Facultad de Ciencias, Universidad de Granada, Avda. Fuentenueva, s/n, Granada 18071, Spain.
Eva Maria
EM
Cañadas
Centro Conservazione Biodiversità (CCB), Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Viale Sant'Ignazio da Laconi, 13, 09123 Cagliari, Italy.
Gianluigi
G
Bacchetta
D003080:Cold Temperature; D018525:Germination / Q000502:physiology*; D007558:Italy; D018653:Juniperus / Q000502:physiology*; D057445:Plant Dormancy; D012621:Seasons; D012639:Seeds / Q000502:physiology*; D013696:Temperature
Cupressaceae; Dormance; Dormancy; Germination; Juniperus macrocarpa; Viability; Viabilité