Dormancy in seeds imposed by the seed coat

Characteristics of winged bean (Psophocarpus tetragonolobus) seeds during soaking and boiling

“…They also found that some bean varieties have a proportion of seeds with differing degrees of impermeability to water, that is related to seed size. Previous work has shown that imbibition is relation to seed size and seed weight (Barton 1965;Heydecker 1972;Hsu et al 1983). In previous work, Sambudi H (unpublished) found that winged bean seeds of a local variety from Central Java, Indonesia, were softer than those from East Java and West Nusa Tenggara, and that some seeds of a Central Java variety, especially the small seeds, remained vary hard even after soaking and boiling in 10 g litre-' sodium bicarbonate solution.…”

Removal of mesquite seeds by small rodents in the Monte desert, Argentina

“…Observational data reveal that caches contain 50% of the seeds with evidence of rodent predation. However, the results of field experiments indicate that rodents only remove the exocarp and mesocarp; whereas neither the endocarp nor the seed coat, both closely associated with dormancy and germination inhibition (Barton, 1965;Warrag, 1994), seem to be very affected (0-1.4%). These differing results may be due to the short time that the animals were in contact with the caches during the field experiments.…”

“…In seeds of desert trees (as the genus Prosopis), germination is often hindered by physical dormancy (Burkart, 1952), associated with water-impermeable seed coats (Barton, 1965). Under natural conditions, seed dormancy could be broken by animals, fire, and soil abrasion (e.g.…”

THE CONTROL OF GERMINATION IN STACHYS ALPINA (L.)

“…In addition, the renewed growth of these seeds was anomalous and development was restricted, at least during the early stages, to a localized enlargement of the cotyledons, with little or no development of the radicle. In a number of instances where the seed or fruit coats have been shown to exert some control over seed germination, this regulation appears to be due partly to restricted passage of oxygen through the integuments (Barton, 1965;Roberts, 1969). Increased oxygen tensions often then produce appreciable increases in germination, either of intact seeds (Wareing and Foda, 1957;Major and Roberts, 1968), or of seeds with perforated integuments (Black and Wareing, 1959).…”