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Important roles for biotic agents in integrated weed management include preventing seed production and weed emergence from the seed bank. Seed-attacking microorganisms have been described for a limited number of economically important weeds and serve as examples illustrating the potential for reducing weed seed production. Innundative releases of seed-feeding insects have also successfully redu...

Seed banks are common characteristics to many plant species, which allow storage of genetic diversity in the soil as dormant seeds for various periods of time. We investigate an above-ground population following a Fisher-Wright model with selection coupled with a deterministic seed bank assuming the length of the seed bank is kept constant and the number of seeds is large. To assess the combine...

Gene banks around the world hold over 370.000 accessions of barley (van Hintum and Menting, 2003). Although a large number of landraces and obsolete cultivars are stored in genebanks the geographic coverage of this conserved material is far from evenly distributed. For example only a handful of landraces from Northern Europe have been conserved (Jones et al, 2008a). Thus studies of geographic d...

This article reports experiments that explore the critical factors for gene flow in oilseed rape (Brassica napus) via the soil seedbank under Chinese farming systems. Research was carried out on 16 farmer s fields to estimate harvest seed losses after different planting methods and harvest timings, during the four components of the harvest operations. An additional field experiment was set up t...

The occurrence of various species of Brassicaceae with indehiscent fruits in the cold deserts of NW China suggests that there are adaptive advantages of this trait. We hypothesized that the pericarp of the single-seeded silicles of Isatis violascens restricts embryo expansion and thus prevents germination for 1 or more years. Thus, our aim was to investigate the role of the pericarp in seed dor...

Gorse (Ulex europaeus L.) is a major agricultural and environmental weed in many parts of the world and has a persistent seedbank. Several techniques were investigated to either kill the seed or encourage it to germinate. Scarification of the seed coat resulted in almost complete germination of seeds. Smoked water had little effect on intact seed and high concentrations killed scarified seed. G...

Dormant seeds in permanent soil seed banks change their germination probability with age, but little is known about the causes of this behavior. Since current adaptive models do not consider the age structure of the seed bank, the sole explanation is that changes in germination probability with age are due to passive accidental factors or to decay of seeds. Here we present a theory, which shows...

Although policymakers often discuss tradeoffs between bank competition and stability, past research provides differing theoretical perspectives and empirical results on the impact of competition on risk. In this paper, we employ a new approach for identifying exogenous changes in the competitive pressures facing individual banks and discover that an intensification of competition materially boo...

electron micrographs of many plant features and details of their reproduction. “Our work results from an enthusiasm to communicate and express our shared passion and fascination for the beauty of sexual reproduction among flowering plants,” the authors write. Their aim is to engage audiences for the research and conservation work in the plant sciences carried out throughout the world. And they ...