PS 52-72
The occurrence of seed heteromorphism in the deserts of the southwestern USA and northwestern Mexico
Seed heteromorphism is a plant reproductive strategy in which plants produce more than one type of seed at the same time. Through a literature review we studied seed heteromorphism in the deserts of the southwestern USA and northwestern Mexico. Our primary goal was to summarize the occurrence and distribution of seed heteromorphism. We categorized seed heteromorphic plants with respect to the type of seed heteromorphic strategy. Although seed heteromorphism has been thoroughly studied in several plants in North America and Mexico, no investigations to date have summarized its prevalence across all extant species in this area.
Results/Conclusions
In our literature search we found 37 species of seed heteromorphic plants spread across 11 families. Seed heteromorphism was concentrated in the Boraginaceae and Asteraceae which contributed eight and ten species, respectively. In addition, 75% of seed heteromorphic species were of annual or ephemeral duration. This suggests that seed heteromorphism may be especially advantageous in annual species.