lead to continuing effects for increasing extensive of yield by means of advanced agronomic operations and selection of high yielding resistant genotypes. there fore, due to evaluation and determination of best effective traits in improvement of yield and grain quality of local populations of winter wheat, an experiment was carried out in uremia agricultural research station, on 30 local popula...

Habitat fragmentation can have severe effects on plant pollinator interactions, for example changing the foraging behaviour of pollinators. To date, the impact of plant population size on pollen collection by pollinators has not yet been investigated. From 2008 to 2010, we monitored nine bumble bee species (Bombus campestris, Bombus hortorum s.l., Bombus hypnorum, Bombus lapidarius, Bombus pasc...

Sagebrush (Artemisia spp.) obligate wildlife species such as the imperiled greater sage-grouse (Centrocercus urophasianus) face numerous threats including altered ecosystem processes that have led to conifer expansion into shrub-steppe. Conifer removal is accelerating despite a lack of empirical evidence on grouse population response. Using a before-after-control-impact design at the landscape ...

In this paper, a simple semi-discrete (ticks' feeding is assumed to occur only during the summers of each year) model for tick population dynamics is presented. Conditions for existence, uniqueness, and stability of a positive equilibrium are found; the system is then studied numerically using parameter estimates calibrated for the tick Ixodes ricinus in Trentino, Italy, and the sensitivity to ...

INTRODUCTION Small food stores are prevalent in urban neighborhoods, but the availability of nutritious food at such stores is not well known. The objective of this study was to determine whether data from 3 sources would yield a single, homogenous, healthful food store category that can be used to accurately characterize community nutrition environments for public health research. METHODS We...

Intercropping fennel (Foeniculum vulgare Mill.) with naturally colored cotton (Gossypium hirsutum L.) may provide a beneficial socioeconomic, ecological and environmental alternative for recuperating agribusiness in fennel and cotton cultivations in northeast Brazil because these crops do not compete for nutrients. The objectives of this study were to investigate the vertical and horizontal dis...