1 Results from patch-occupancy metapopulation models indicate that a trade-off between competitive and colonization abilities is necessary for species to coexist in patchy environments. However, such models are often based on unrealistic ecological assumptions, such as global dispersal and no local population dynamics. 2 We develop a plant metapopulation model that allows us to sequentially rel...

The nature of weeds is a complex adaptive, soil-seed communication system. The nature of weedy Setaria life history is an adaptable, changeable system in which complex behaviors emerge when self-similar plant components self-organize into functional traits possessing biological information about spatial structure and temporal behavior. The nature of the weedy Setaria is revealed in the physical...

Recent studies indicate that strong systems of property rights are not a necessary condition for the operation of the soybean seed market in the Americas (Wright; Pardey, 2006; Endres; Goldsmith, 2007). These studies are based on a dichotomy. The North – represented by the U.S. – is a strong institutional environment in which agrobiotechnology firms adopt an optimal strategy, setting technologi...

The weed seed bank of a long-term tillage study in subarctic Alaska was studied at the end of 10 years of continuous spring barley (Hordeum vulgare L.). Tillage treatments were: no-till, disked once (spring), disked twice (spring and fall), and chisel plow (fall). Soil cores were obtained from each tillage treatment and seeds were manually separated from soil after washing through sieves. Tilla...

Recent theoretical research has shown that ocean currents and wind interact to disperse seeds over long distances among isolated landmasses. Dispersal of seeds among isolated oceanic islands, by birds, oceans and man, is a well-known phenomenon, and many widespread island plants have traits that facilitate this process. Crucially, however, there have been no mechanistic vector-based models of l...

Changes in the levels of thiamin-binding globulin and thiamin in wheat seeds during maturation and germination were studied. The thiamin-binding activity of the seed proteins increased with seed development after flowering. The thiamin content of the seeds also increased with development. Thiamin-binding activity decreased during seed germination. On the other hand, immunological analysis using...

It is commonly accepted that species interactions such as granivory are more intense in the tropics. However, this has rarely been tested. A global dataset of post-dispersal seed removal by invertebrates and vertebrates for 79 native plant species from semi-natural and natural terrestrial habitats ranging from 55° N to 45° S, was compiled from the global literature to test the hypothesis that p...

A seed shadow is the spatial distribution of all seeds dispersed from an individual plant (Janzen, 1970; Nathan and Muller-Landau, 2000; Schupp et al., 2002). The sum of seed shadows across all individuals in a population plus those seeds dispersed from other populations makes up seed rain. For vertebrate-dispersed species, seed shadows are the primary outcome of plant–frugivore interactions, y...

BACKGROUND Knowledge about how change the importance of soil seed bank and relationship between seed mass and abundance during vegetation succession is crucial for understanding vegetation dynamics. Many studies have been conducted, but their ecological mechanisms of community assembly are not fully understood. METHODOLOGY We examined the seasonal dynamics of the vegetation and soil seed bank...

Soil seed banks serve as reservoirs for future plant communities, and when diverse and abundant can buffer vegetation communities against environmental fluctuations. Sparse seed banks, however, may lead to future declines of already rare species. Seed banks in wetland communities are often robust and can persist over long time periods making wetlands model systems for studying the spatial and t...