The litter of many plant species is known to inhibit germination, and this phenomenon is commonly interpreted as allelopathic inhibition of one species by another. However, an alternative interpretation is that seeds may be using environmental signals to inform the timing of their germination and thereby use dormancy as a mechanism of habitat choice. Nicotiana attenuata Torr. ex Wats. (Solanace...

THE ECOLOGICAL RELEVANCE OF MATURATION DRYING DETERMINES DEHYDRIN EXPRESSION IN SEEDS In areas exhibiting typical seasonal changes, the seeds of most plants are getting mature in summer and fall, respectively. In order to prevent the destruction of the young and sensitive seedlings by the frosty winter conditions, any germination in fall has to be hindered. Accordingly, efficient outlasting mec...

Seed dormancy is a common phase of the plant life cycle, and several parts of the seed can contribute to dormancy. Whole seeds, seeds lacking the testa, embryos, and isolated aleurone layers of Arabidopsis (Arabidopsis thaliana) were used in experiments designed to identify components of the Arabidopsis seed that contribute to seed dormancy and to learn more about how dormancy and germination a...

Summer annuals overwinter as seeds in the soil seed bank. This is facilitated by a cold-induced increase in dormancy during seed maturation followed by a switch to a state during seed imbibition in which cold instead promotes germination. Here, we show that the seed maturation transcriptome in Arabidopsis thaliana is highly temperature sensitive and reveal that low temperature during seed matur...

Gibberellic acid at 0.1 mum stimulates amylase synthesis in dormant Avena fatua seeds without inducing germination; at 0.5 mm it enhances biosynthesis of proteins and RNA in both the embryo and the endosperm and utilization of the endosperm sugars by the embryo. These events occur in early hours (0-14th hour) and prior to germination, which begins 24 hours after gibberellic acid application. Th...

Plants perceive and integrate information from the environment to time critical transitions in their life cycle. Some mechanisms underlying this quantitative signal processing have been described, whereas others await discovery. Seeds have evolved a mechanism to integrate environmental information by regulating the abundance of the antagonistically acting hormones abscisic acid (ABA) and gibber...

The transition from seed to seedling is mediated by germination, a complex process that starts with imbibition and completes with radicle emergence. To gain insight into the transcriptional program mediating germination, previous studies have compared the transcript profiles of dry, dormant, and germinating after-ripened Arabidopsis (Arabidopsis thaliana) seeds. While informative, these approac...

Introduction In a recent paper NOGuCHI (2) described histological studies made on the structure of Russian sunflower leaves grown from seeds irradiated at the stage of incipient germination, with hard, or short wave-length, x-rays. This paper describes a similar study in which the seeds used were dormant soy beans and the radiation was soft, or long wave-length, x-rays generated by a gas x-ray ...

BACKGROUND AND AIMS Karrikinolide (KAR(1)) is a smoke-derived chemical that can trigger seeds to germinate. A potential application for KAR(1) is for synchronizing the germination of weed seeds, thereby enhancing the efficiency of weed control efforts. Yet not all species germinate readily with KAR(1), and it is not known whether seemingly non-responsive species can be induced to respond. Here ...

Pre-dispersal seed predation can greatly reduce crop size affecting recruitment success. In addition, non-fatal damage by seed predators may allow infection by fungi responsible for post-dispersal seed losses. The objectives of this study were (1) to quantify pre-dispersal seed predation and fungal infection in a Neotropical tree species, Luehea seemannii, that produces dehiscent fruits and win...