Migration of plant populations is a potential survival response to climate change that depends critically on seed dispersal. Biological and physical factors determine dispersal and migration of wind-dispersed species. Recent field and wind tunnel studies demonstrate biological adaptations that bias seed release toward conditions of higher wind velocity, promoting longer dispersal distances and ...

In order to study of the effect of seed inoculation with PGPR on nitrogen and phosphorus use efficiency of spring wheat in different levels of nitrogen and phosphorus fertilizers, an experimental was conducted at the Research Farm of Mohageh Ardabili University, Ardabil, Iran during 2012 year. The combination of nitrogen fertilizer in three levels (0, 40 and 80 kg N/ha as urea) and phosphorus f...

Seed dispersal and germination are critical to the fitness of all tree species. Moreover, among most trees the percentage of seeds that become seedlings, or “seedling success”, is very low. We examined seed success of a dominant lowland rainforest species, Pentaclethra macroloba, across a soil moisture gradient. Previous studies have established that P. macroloba has reduced seed germination ra...

Declines in riparian willow (Salix spp.) communities in Rocky Mountain National Park, Colorado, USA , coincident with a large increase in elk (Cervus elaphus L.) populations, has raised concerns about the future of willow communities. To identify possible constraints on willow establishment in two heavily browsed riparian areas, in 2000 and 2001, we examined seed dispersal phenology, germinabil...

Pollen-mediated gene flow in space is well documented and isolation distances are recommended to ensure genetic purity of Brassica napus seed crops. Isolation in time could also contribute to gene flow management but has been little investigated. We assessed the effects of asynchronous and synchronous flowering on intraspecific B. napus gene flow by seeding adjacent plots of transgenic spring c...

Fertilizer amendments can impact weed populations in a variety of ways. This study evaluated the effects of 12 year-long applications of different fertilization systems on size and composition of the weed seed bank in a conventionally managed maize monoculture field. Fertilization systems included all factorial combinations of two dairy cattle slurry rates, three vegetable, fruit and garden was...

It has been suggested that lower rates of granivory in South American warm deserts compared to their North American counterparts arose from a reduction of seed reserves in the former owing to the extinction of argyrolagid marsupials. We measured seed reserves in two habitats of the central Monte Desert in an attempt to detect such seed decline, but to no avail. After moderate rainfall, maximum ...

The distribution of many tree species is strongly determined by the behavior and range of vertebrate dispersers, particularly birds. Many models for seed dispersal exist, and are built around the assumption that seeds undergo a random walk while they are being carried by vertebrates, either in the digestive tract or during the process of seed storage (caching). We use a PDF of seed handling (ca...

In order to study of the effect of seed inoculation with PGPR on nitrogen and phosphorus use efficiency of spring wheat in different levels of nitrogen and phosphorus fertilizers, an experimental was conducted at the Research Farm of Mohageh Ardabili University, Ardabil, Iran during 2012 year. The combination of nitrogen fertilizer in three levels (0, 40 and 80 kg N/ha as urea) and phosphorus f...

In order to investigate the effect of seed pretreatment with growth regulators on biochemical characteristics of red bean genotypes, a factorial experiment was carried out in a randomized complete block design with three replications. In this research, seed pretreatment with growth regulators namely salicylic acid (SA) and naphthalene acetic acid (NAA) were applied at four levels including P0: ...