to estimate population density of the cabbage aphid, brevicoryne brassicae (l.), a stratified random sampling was conducted in two unsprayed canola fields in isfahan (central iran) during 2011-2012. population density was determined for apterous, and alates, as well as the total population, at two plant growth phases (pgp1: from plant emergence to the end of rosette, and pgp2: from the beginnin...

the population density and spatial distribution pattern of empoasca decipiens paoli were etermined in tehran area, iran, during 2004-2005 on four species of common bean phaseolus vulgaris (l.) var. talash, lima bean p. lunatus (l.) savi ex hassk. var. sadaf, rice bean p. calcaratus roxb. var. goli and cowpea vigna sinensis (l.) var. parastoo. the higher and lower mean population densities of e....

population density and spatial distribution of thrips tabaci lindeman on seven soybean varieties (williams, tellar, sahar, dpx, l17, sari and zane) and one genotype (ks3494) were studied in tehran region, during 2007. the highest population density of the thrips per leaf was recorded on dpx and on ks3494 (0.810.05 and 0.800.05, respectively). the lowest population density was observed on l17 ...

the population densities and spatial distribution patterns of zetzellia pourmirzai khanjani and ueckermann and its preys cenopalpus irani dosse and bryobia rubrioculus (scheuten) were studied in a sprayed orchard in kermanshah, a western province of iran, from 31 may till 7 november, 2007. the interaction (density dependence) between the plant feeding mites and their predator was determined as ...

although knowing the time of the occurrence of the earthquakes is vital and helpful, unfortunately it is still unpredictable. by the way there is an urgent need to find a method to foresee this catastrophic event. there are a lot of methods for forecasting the time of earthquake occurrence. another method for predicting that is to know probability density function of time interval between earth...

the analysis of net catches made in absheron gulfs of the caspian sea during 2011-2012 is provided. the ichthyofauna of absheron gulfs, including 26 species found in the north gulf, and 33 species and subspecies found in the south gulf was studied for the first time. a taxonomical and ecological diversity of the fish fauna of north and south absheron gulfs is characterized. the peculiarities of...

We inverse the surface gravity data to recover subsurface 3D density distribution with two strategy. In the first strategy, we assumed wide density model bound for inverting gravity data and In the second strategy, the inversion procedure have been carried out by limited bound density. Wediscretize the earth model into rectangular cells of constant andunidentified density. The number of cells i...