Density-Dependent Seed Germination Strategies in Colonizing Versus Non- Colonizing Plant Species

Abstract

Seeds of 11 spp. of plants were germinated singly or in groups to assay the effect of density on germination. Literature reports on 11 more species are also considered. Of 15 colonizing species, 7 show a negative response, 7 no response, and 1 (also grown as a crop) a positive response. Four of the 6 non-colonizing species and 1 forage species show a positive response. Reduced germination at high densities may be a population-regulating mechanism. Increased germination may increase the probability of survival of at least 1 individual at a favorable site. [The plants discussed are in the families: Cruciferae, Chenopodiaceae, Graminae, Compositae, Scrophulariaceae, Onagraceae, Campanulaceae, Plantaginaceae, Caryophyllaceae, Leguminosae, Saxifragaceae.].