The ongoing destruction of old-growth forests puts tropical forest species under great pressure because of the resulting habitat loss. A pre-requisite for the maintenance of a viable metacommunity in a fragmented landscape is the connectivity between habitable patches. We experimentally studied four vital steps of epiphyte dispersal in different habitat types in western Panama. (i) Seed falling...

Insect herbivory is common, but the conditions under which it reduces the fitness and population size of plants remain poorly understood. We quantified populationlevel impacts of floral herbivory by specialized insects on cobweb thistle (Cirsium occidentale var. occidentale) in a California coastal dune ecosystem, and then compared these demographic effects to those published for Platte thistle...

PREMISE OF THE STUDY Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an activ...

Seed dormancy controls germination and plays a critical role in regulating the beginning of the life cycle of plants. Seed dormancy is established and maintained during seed maturation and is gradually broken during dry storage (after-ripening). The plant hormone abscisic acid (ABA) and DELAY OF GERMINATION1 (DOG1) protein are essential regulators of seed dormancy. Recent studies revealed that ...

In an environment perturbed by malicious interference, establishing a reliable wireless connection without shared secrets typically relies on uncoordinated spread spectrum methods, such as UFHSS or UDSSS. These methods offer a lowthroughput channel for the exchange of key contributions with the goal to establish a shared secret. They, however, incur a significant delay when confronted with adve...

it is well known that sugar beet is sensitive to salinity stress at the germination stage. three separate experiments were conducted to study the effects of salinity on seed germination, plant establishment, and yield of sugar beet genotypes for screening purposes. these included: (a) a laboratory study using four water salinity levels (with ec values < 0.1 as the control, 16, 20, and 24 ds m-1...

Seed thermoinhibition (inhibition of germination at warm temperatures) can reduce seedling emergence and stand establishment of cultivated lettuce (Lactuca sativa L.) when soil temperatures are warm (>25°C) at planting. Genetic variation for high temperature germination tolerance exists among accessions of lettuce and related wild species. Seeds of a L. serriola accession (UC96US23) germinated ...