Weedy Setaria Seed Life History

This book is the story of the search to discover the biological basis of seed behavior in the weedy Setaria species-group. It consists of seven chapters, five experimental, a concluding essay and an introduction. The first two are from studies by Milt Haar. In the first, stable and plastic seed productivity behaviors are studied in terms of plant architecture. In the second, the structure of seed dormancy (seed heteroblasty) is elucidated. In the next three by Kari Jovaag (based on field experimental work by Brad Atchison), seed heteroblasty defines the evolutionary ecological role this complex functional trait plays in determining seedling emergence. In the third article seed heteroblasty in several populations is defined. In the fourth article, the role seed heteroblasty plays in the annual cycling of germinability-dormancy in soil seed pools is described. In the final of this series, seedling emergence (pattern and magnitude) of the populations studied is presented. The conclusion of this work is that the number and quality of the seed produced during embryogenesis is the predicate, the blueprint, for seedling recruitment timing and extent.