Ð Although there has been a considerable growth of private seed enterprises in developing countries, there are few examples of the private delivery of seed of public crop varieties that are not hybrids. This paper discusses the example of rice in Andhra Pradesh, where private enterprise is supplying an increasing proportion of the seed used by farmers. The institutional conditions for private e...

Successful crop production depends initially on the availability of high-quality seed. By 2050 global climate change will have influenced crop yields, but will these changes affect seed quality? The present review examines the effects of elevated carbon dioxide (CO2) and temperature during seed production on three seed quality components: seed mass, germination and seed vigour. In response to e...

Dormancy is a state of metabolic arrest that facilitates the survival of organisms during environmental conditions incompatible with their regular course of life. Many organisms have deep dormant stages to promote an extended life span (increased longevity). In contrast, plants have seed dormancy and seed longevity described as two traits. Seed dormancy is defined as a temporary failure of a vi...

The timing of harvest is a major factor affecting seed quality in soybean, particularly in Midsouthern USA, when rain during harvest period is not uncommon. The objective of this research was to evaluate the effects of time of harvest on soybean seed quality (seed composition, germination, seed coat boron, and lignin) in high germinability (HG) breeding lines (50% exotic) developed under high h...

Seed weight is a very important and complex trait in rapeseed (Brassica napus L.). The seed weight of rapeseed shows great variation in its natural germplasm resources; however, the morphological, cytological and genetic causes of this variation have remained unclear. In the present study, nine highly pure inbred rapeseed lines with large seed weight variation and different genetic backgrounds ...

abstract a sub-sample of lentil (lens culinaris medik. cv. kimia) seeds was kept as bulk (s1) and another sample was separated to large (s2) and small (s3) seeds. a sub-sample of each size was kept as control or high vigor seed lot (a1) and the two other sub-samples were artificially aged for 2 and 4 days (a2 and a3, respectively). field performance and some physiological traits of plants from ...

seed storage proteins are synthesized as sources of carbon, nitrogen and sulfur for the next generation of plants. reactive oxygen species serve as second messengers for signal transduction; however, molecular targets of oxidant signaling have not been defined. here, many researchers showes that ligand–receptor mediated signaling promotes reactive oxygen species– dependent protein carbonylation...

1. We investigated the relationships of seed size, dispersal mode and other species characteristics to interspecific variation in mean primary seed dispersal distances, mean annual seed production per unit basal area, and clumping of seed deposition among 41 tropical tree species on Barro Colorado Island, Panama. 2. A hierarchical Bayesian model incorporating interannual variation in seed produ...

Many studies have focused on the ecology of seed dimorphism, the production of two seed types by a single plant. Morphology and seed size are usually correlated, but how morphology affects germination percentage and seedling growth is poorly understood. Here we explicitly separate these effects for nine populations of the dimorphic species Tragopogon pratensis subsp. pratensis. Larger seeds yie...

BACKGROUND AND AIMS Seed survival in the soil contributes to population persistence and community diversity, creating a need for reliable measures of soil seed bank persistence. Several methods estimate soil seed bank persistence, most of which count seedlings emerging from soil samples. Seasonality, depth distribution and presence (or absence) in vegetation are then used to classify a species'...