Maternal control of seed size in the common bean provides an opportunity to study genotype-independent seed weight effects on early seedling growth and development. We set out to test the hypothesis that the early heterotrophic growth of bean seedlings is determined by both the relative amount of cotyledon storage reserves and the genotype of the seedling, provided the hybrid genotype could be ...

ABSTRACT- This experiment was carried out during the growing seasons of 2010 and 2011 at the Agricultural Research Farm of Bu-Ali Sina University, to study the effect of weed competition on subsequent germination and seed vigour of chickpea. 12 weed interference durations were evaluated in a randomized complete block design with three replications. Experiments consisted of two sets of treatment...

The intersubspecific hybrids of autotetraploid rice has many features that increase rice yield, but lower seed set is a major hindrance in its utilization. Pollen sterility is one of the most important factors which cause intersubspecific hybrid sterility. The hybrids with greater variation in seed set were used to study how the F(1) pollen sterile loci (S-a, S-b, and S-c) interact with each ot...

We introduce and study new models for learning from contagion processes in a network. A learning algorithm is allowed to either choose or passively observe an initial set of seed infections. This seed set then induces a final set of infections resulting from the underlying stochastic contagion dynamics. Our models differ from prior work in that detailed vertex-byvertex timestamps for the spread...

We quantified the fruit set of four Acacia spp. inside and outside of long-term experimental exclosures in order to examine the fitness consequences of herbivory by large mammals. We found a considerable interspecific variation in the reproductive fitness costs of herbivory in four African Acacia spp. Acacia nilotica and A. brevispica respond to protection from large mammalian herbivores by gre...

Offspring number and size are key traits determining an individual's fitness and a crop's yield. Yet, extensive natural variation within species is observed for these traits. Such variation is typically explained by trade-offs between fecundity and quality, for which an optimal solution is environmentally dependent. Understanding the genetic basis of seed size and number, as well as any possibl...

The bilobed stigma of many species in the order Scrophulariales closes in response to touch by an animal pollinator. In hummingbird-pollinated bush monkey flower, Mimulus aurantiacus (Scrophulariaceae), closure is rapid, occurring within seconds of tactile stimulus. We investigated the proximate causes of stigma closure and subsequent reopening in M. aurantiacus, as well as potential costs and ...

Potential decreases in crop yield from reductions in bee-mediated pollination services threaten food production demands of a growing population. Many fruit and vegetable growers supplement their fields with bee colonies during crop bloom. The extent to which crop production requires supplementary pollination services beyond those provided by wild bees is not well documented. Pumpkin, Cucurbita ...