Germination and soil seed bank traits of Podocarpus angustifolius (Podocarpaceae): an endemic tree species from Cuban rain forests

Abstract

Podocarpus angustifolius is an endangered recalcitrant-seeded small tree, endemic to mountain rain forests in the central and Pinar del Río regions in Cuba. In this study, the germination patterns of P. angustifolius seeds were evaluated and the nature of the soil seed bank was determined. Using a weighted two-factor design, we analyzed the combined germination response to seed source (i.e. freshly matured seeds directly collected from trees versus seeds extracted from soil samples) and pretreatment (i.e. seed water-immersion for 48h at room temperature). Germination was delayed for four weeks (≈30 days) in all cases, regardless of both factors analyzed. Moreover, nine additional days were necessary to achieve high germination values (in the case of fresh, pretreated seeds). These results overall may indicate the existence of a non-deep simple morphophysiological dormancy in P. angustifolius seeds. The water-immersion significantly enhanced seed germination, probably as a result of the hydration of recalcitrant seeds. Although germination of seeds extracted from soil samples was low, probably due to aging and pathogen effects throughout the time of burial, the study revealed the existence of a persistent soil seed bank (at least short-termed) of ≈42 viable seeds per m 2 in the upper 10cm of soil. Such a record is noteworthy since references to persistent soil seed banks in recalcitrant-seeded species are scarce in the literature. The population consequences derived from the formation of persistent soil seed banks in this endangered species are discussed.

Understanding biological characteristics of Acacia melanoxylon in relation to fire to implement control measurements

“…The soil seed bank was very abundant and delved deeper into the ground, which is common in mature populations. The increase in seed density with increasing soil depth and the clear separation of the litter from the rest of the soil indicates a bank persistent over time (Ferrandis et al 2011). The total soil seed bank contained about 44,640 seeds m −2 , a density very similar to that found on the same species by Milton and Hall (1981) in South Africa.…”

The ecophysiology of seed persistence: a mechanistic view of the journey to germination or demise

“…These seeds perish if they dry below a critical water content, but some desiccation‐sensitive seeds can survive for several months in moist conditions (Le Tam et al , ), due to dormancy (Greggains et al , ; Jayasuriya et al , ) or delayed germination (Pina‐Rodrigues & Figliolia, ). For example, seeds of Podocarpus angustifolius form a persistent soil seed bank (Ferrandis, Bonilla & Osorio, ), which is highly unusual, but indicates that desiccation tolerance is not a strict prerequisite for seed persistence.…”

Underdeveloped embryos and kinds of dormancy in seeds of two gymnosperms: Podocarpus costalis and Nageia nagi (Podocarpaceae)

“…Among the nine families in Pinopsida, only Podocarpaceae and Taxaceae are reported to have underdeveloped embryos. It also has been observed that embryos in seeds of Podocarpaceae are small in relation to the size of the female gametophyte (Ng, 1992;Ferrandis et al, 2011), and several studies on Podocarpaceae have revealed that varying periods of time are required for seeds to germinate. It also has been observed that embryos in seeds of Podocarpaceae are small in relation to the size of the female gametophyte (Ng, 1992;Ferrandis et al, 2011), and several studies on Podocarpaceae have revealed that varying periods of time are required for seeds to germinate.…”