Under commercial poinsettia production conditions we compared two patterns of parasitoid release for the aphelinid whitefly parasitoid Eretmocerus eremicus Rose and Zolnerowich. We compared the currently used pattern of a fixed weekly release number (3 females per plant per week) to an experimental pattern in which more parasitoids were released early in the crop (wks 1-8), followed by a lower ...

The way an invasion progresses through space is a theme of interest common to invasion ecology and biological pest control. Models and mark-release studies of arthropods have been used extensively to extend and inform invasion processes of establishment and spread. However, the extremely common single-scale approach of monitoring initial spread leads to misinterpretation of rate and mode. Using...

A large-scale study was conducted in 1996 to evaluate and demonstrate strategies for pest management of Bemisia tabaci (Gennadius) in cotton involving different insecticide regimes, application methods, and action thresholds. Here we examined the effects of the various management systems on the abundance and activity of native natural enemies. Population densities of 18 out of 20 taxa of arthro...

nitrate pollutants increase the growth of algal bloom, resulting in fresh water eutrophication. the high nitrogen level in wastewater has become a growing concern, which has risen the necessity to develop efficient nitrogen removal techniques. biological denitrification, which is the reduction of oxidized nitrogen compounds like nitrate or nitrite to gaseous nitrogen compounds, is the most impo...

a green low-cost and reproducible yeast mediated synthesis of silver nanoparticles is reported. the synthesis is performed at room temperature. x-ray and transmission electron microscopy analyses are performed to ascertain the formation of ag nanoparticles. nanoparticles almost spherical in shape having a size of 6-20 nm are found.

desert truffles, hypogeous pezizales (ascomycota), are difficult to identify due to evolutionary convergence of morphological characters among taxa that share a similar habitat and mode of spore dispersal. in this paper we document the presence of picoa lefebvrei (pat.) maire (=phaeangium lefebvrei) in iran and use phylogenetic analysis of the its and 28s rdna to show that this species belongs ...

cyanobacteria are well known for their production of a multitude of highly toxic substances . the genus stigomena is regarded as good candidates for producing biologically active secondary metabolites, which are highly toxic to humans and other animals. the carcass of a dog was found at the shore of lake ali-abad, iran. biomass from the discovery site appeared to be of cyanobacterial nature. we...