Seed anatomy and dormancy class of 14 species from the Andean montane forests of Colombia

Abstract

Seed dormancy is a key trait used around the world to help understand the ecological dynamics of plant species, however, in some ecosystems such as the Andean forests of Colombia, the identification of dormancy class remains poorly known. To address this, we described the morphology, anatomy and dormancy class of the seeds and fruits of 14 species using microtome sections, light microscopy and scanning electron microscopy. Five native pioneer species showed Morphophysiological Dormancy, three Physical Dormancy + Physiological Dormancy and two Physical Dormancy, whereas two invasive species showed Physiological Dormancy. Only the species of the genus Cecropia had seeds with PY + PD that was promoted by the anatomical structure of the achenes. Of the analysed species, 85% showed dormancy and followed a pattern like other tropical montane ecosystems in the world. The anatomy of achenes and development of seed dormancy play important roles in the capacity of Cecropia species to contribute to the natural regeneration of Andean ecosystems. Additionally, seed dormancy may promote the high invasiveness of Thunbergia alata and Ulex europaeus in the Andean forests of the Central Cordillera of Colombia.

Seed permeability: an essential trait for classifying seed dormancy type

“…The authors found dormancy in 85% of their study species, three of which are in the genera Cecropia and were classified as having both physiological and physical dormancy (referred to as physiophysical dormancy). Seeds with physiophysical dormancy have impermeable coats, a fully developed embryo, and a mean germination time (MGT) of over 30 days (Rojas-Villa and Quijano-Abril, 2023). Here, we present seed permeability data measured by fluorescent dye uptake into the seed endosperm and germination trails from a Panamanian lowland population of Cecropia peltata (one of the species studied by Rojas-Villa & Quijano-Abril, 2023), as well as Ochroma pyramidale, Cecropia longipes, and Cecropia insignis.…”

“…Seeds with physiophysical dormancy have impermeable coats, a fully developed embryo, and a mean germination time (MGT) of over 30 days (Rojas-Villa and Quijano-Abril, 2023). Here, we present seed permeability data measured by fluorescent dye uptake into the seed endosperm and germination trails from a Panamanian lowland population of Cecropia peltata (one of the species studied by Rojas-Villa & Quijano-Abril, 2023), as well as Ochroma pyramidale, Cecropia longipes, and Cecropia insignis. Our data do not support the presence of physical dormancy in seeds of Cecropia, while O. pyramidale does exhibit physical dormancy.…”