Seed traits, germination and seed dormancy of Juniperus barbadensis subsp. lucayana (Cupressaceae), endemic tree of Caribbean

Abstract

Juniperus barbadensis is a conifer endemic to the Caribbean and one of the two species of the genus that inhabits Cuba. It constitutes a species of high timber, medicinal and ornamental value. At present, it is in Critically Endangered, mainly due to habitat loss and overexploitation. Natural regeneration of wild populations is low, and little is known about its seed biology. In order to contribute to its propagation and conservation, morphophysiological characteristics of the seeds, germination requirements and seed dormancy classes were studied. Germination was evaluated in laboratory conditions under constant light and darkness at a fixed temperature of 25ºC and alternating temperatures of 25/30ºC and 25/35ºC. The fruits presented three seeds each, small, with 21% average humidity, linear embryo developed, permeable to water and tolerant to desiccation according to biometric data. A small fraction of the lot was considered non-dormant, but most of the seeds showed physiological dormancy. Germination was favored in light and the highest percentages were reached at 25ºC. Future research is suggested that could complete the results obtained and recommendations for planting in nurseries are provided.