in order to study the effects of plant density and nitrogen rates on yield, nitrate and protein of silage maize (ksc 704) in shahrekord area, an experiment was conducted during 2007 growing season at the agricultural research farm of shahrekord university. the experimental design of the experiment was randomized complete blocks with factorial arrangement with four replications. treatment consis...

a field experiment was conducted in order to study the effect of nitrogen fertilizer and plant density on yield and quality of maize (zea mays l.) cultivar, mv500 silage as second crop. this study was conducted in agricultural research station of kurdistan university during 2012 growing season. the experiment was laid out as split plot based on randomized complete block design with three replic...

abstractbackground and objectives: in most saline and non-saline soils, nitrogen is the most restrictive nutrient for plant growth. in saline soils, interactive effects of salinity and soil fertility is very important from optimum production. nutrient imbalance is one of the problems with saline soils. in these circumstances, the fertilizer application may to increase osmotic effect of salt, th...

 The aquatic fern Azolla, a small-leaf floating plant that lives in symbiosis with a nitrogen fixing cyanobacteria (Anabaena), is an outstanding plant, thanks to its high biomass productivity along with its tremendous rate per unit area for nitrogen-fixation.  The present study investigates the potential growth of Azolla in secondary effluents for removal of COD, phosphorus, and nitrogen. Resul...

the effects of different levels of nitrogen (100, 200, 300 and 400 mg/l) and potassium (125, 250 and 375 mg/l) on yield and leaf n and k concentrations of tomato were investigated in perlit culture using a factorial randomized design with three replications. the highest fruit yield was obtained with 200 mg/l n. higher levels of nitrogen decreased tomato yield. with increasing nitrogen concentra...

introduction between oil seeds, from the quality, quantity and nutrition index point of view, canola has the top level . because of the solubility of n fertilizers, the time of urea application, is very important and one of the main reasons of the reduction in n application efficiency is utilization of urea in an inappropriate time. by precisely foliar application of nitrogen, the efficiency of...

abstract this study was conducted under cold climate condition in khorasan during 2006-2008 growing seasons to evaluation of soil fertility in wheat-based double cropping systems under different rate of nitrogen and return of crop residues. a randomized complete block design with split-split plot arrangement and three replicates was used. main plots were five crop rotations namely: wheat-wheat,...

background: nitrogen oxides occur in the atmosphere in six forms of namely: n2o , no , no2 , n2o3, n2o4 and n2o5 .among these oxides no2 is the most important air pollutant because of its relatively high toxicity and its ubiquity in ambient air. in this research griess-saltzman method was utilized for determination of nitric oxide and nitrogen dioxide in the atmosphere of different laboratories...