Fecundity and Seed Dormancy Variation Within and Among Echinochloa Species

The Echinochloa genus contains two of the world's top five worst weeds. persistence and weediness spp. are partly due to its seed longevity variable dormancy. In USA, specifically in Arkansas, multiple species infest same field many cases. Persistence could vary across dormancy affects infestation level. Studies were conducted evaluate production potential State. Ninety-four accessions characterized a common garden Fayetteville, USA. colona (L.) Link, E. crus-galli P. Beauv , muricata walteri (Pursh). Only one accession was identified as excluded from data analysis. Seeds after-ripened for 6 months at room temperature germinated 32°C day/23°C night with 12-h daylength. Germination monitored 14 d. Arkansas predominantly (78%). had highest lowest among species. Dormancy within each varied greatly, especially germination capacity (GC) 41–99%. 2.7% 73 dormant. 56–79% GC; 33% 2–39% germination, all considered fecundity, 72,973 seeds per plant. This 2.3- 2.6x higher than that respectively. High high must have contributed dominance other is expected persist longer soil seedbank compared . Seed production, will affect interspecies population dynamics response management tactics.