Ecophysiology of Seed Germination in the Tropical Humid Forests of the World: A Review

Abstract

Most forest tree seeds from the humid tropics germinate soon after dispersal forming carpets of semi-dormant seedlings. Delayed germination and enforced dormancy is frequent among light- gap adapted species, some emergent trees and species with hard-coated seeds. Dormancy is more important as an adaptative trait in marked seasonal forests. The seed bank of the forest soils studied are composed mainly of fast growing pioneer tree seeds and some weed seeds. The dormancy of pioneer trees and other light-gap colonizers is often enforced by light and temperature conditions of forest soil and finishes when a gap is formed. Much research on seed ecophysiology is needed in order to understand the seed germination regulating mechanisms in tropical forests.