Seed Dormancy in Velvetleaf

Seed dormancy in velvetleaf (Abutilon theophrasti Medic.) was due primarily to an impermeable seed coat. Embryo dormancy was not a factor in the occurrence or maintenance of seed dormancy. The presence of germination inhibitors was indicated, but their role in seed dormancy appeared limited. The termination of dormancy under field conditions was considered to result from naturally occurring fractures in the seed coat. The point of fracture was always in the region of the chalazal slit and was considered to follow intense drying under natural conditions. Drying seed in laboratory experiments produced the same fractures in seed coats.