Many herbivore populations fluctuate temporally, but the causes of those fluctuations remain unclear. Plant inducible resistance can theoretically cause herbivore population fluctuations, because herbivory may induce plant changes that reduce the survival or reproduction of later-feeding herbivores. Herbivory can also simply reduce the quantity of food available for later feeders and this, too,...

It is critical to incorporate the process of population dynamics into community genetics studies to identify the mechanisms of the linkage between host plant genetics and associated communities. We studied the effects of plant genotypic diversity of tall goldenrod Solidago altissima on the population dynamics of the aphid Uroleucon nigrotuberculatum. We found genotypic variation in plant resist...

Delayed transition from the vegetative stage to the reproductive stage of development and increased plant height have been shown to increase biomass productivity in grasses. The goal of this project was to detect quantitative trait loci using extremes from a large synthetic population, as well as a related recombinant inbred line mapping population for these two traits. Ten thousand individuals...

This research was conducted in 2007 and 2008 cropping seasons in the experimental field of Shahid Salemi, Ahvaz, south west of Iran. In each year, the study consisted of a split split-plot experiment, using Randomized Complete Block Design (RCBD) with three replications. Four irrigation levels including irrigationoff at the 8 leaf, the 12 leaf and the tasseling stages and optimum irrigation wer...

The neutral theory of biodiversity (NTB) provides an individual-based modeling framework to study eco-evolutionary dynamics. Previous NTB models usually assumed the same per capita rate of speciation across lineages. However, population dynamics may induce macroevolutionary feedbacks that can result in variable per capita speciation rates across lineages. In this paper, with analytical and simu...

to determine the optimum weed management method and plant population density on chickpea yield, a split plot experiment based on rcbd with four replications was carried out at the university of tehran research farm (located in karaj) during 2010-2011. the main factor consisted of nine treatments including: 1. trifluralin pre-plant, 2. pendimethalin pre-plant, 3. complete weeding, 4. imazethapyr...

The ecology of woodland herbaceous species is reviewed. Many factors affect woodland herbs but there have been few studies of their impacts on long-term patterns. Results from a 10-year study of two species in a deciduous forest in Maryland are presented. Populations of Cynoglossum virginianum were influenced by their proximity to tree gap disturbances. Populations of Tipularia discolor were pr...