Nitrogen is the most important essential nutrient that plays a major role in achieving maximum crop yield in agriculture. Therefore, nitrogen fertilizers such as ammonium sulfate and urea have been extensively used in modern agriculture. These fertilizers are generally oxidized to nitrate via nitrite by nitrifying microorganisms in the agricultural field (4, 10, 11). The serious environmental p...

background and objectives: although chemical fertilizers in short-term can increase vegetables yield, but must be renewed each planting season that this trend increases the concentration of nitrate in the vegetables shoots, nitrogen leaching and contamination of water resources, loss of beneficial insects and microorganisms and soil fertility will decline, and over time reduce the yield and qua...

in order to study the effect of different organic fertilizers on quantitative and qualitative characteristics of fenugreek forage, an experiment was conducted based on completely randomized block design with six treatments and three replications at agricultural research station, college of agriculture, ferdowsi university of mashhad, iran, during 2006. the experimental treatments were four orga...

this research, for lowering the use of chemical fertilizer, was carried out using combinations of biological and chemical fertilizer on bean in rasht region in 2012 growing season. the experiment was conducted based on randomized complete blocks design with 12 treatments and three replications. experimental treatments included: control (no fertilizers and no inoculants), chemical fertilizers (n...

effects of various fertilizers such as farmyard manure (fm), urea, and plant growth promoting rhizobacteria (pgpr, including the genera azotobacter and azospirillium) were checked on yield, fatty acids, protein, and oil contents of sunflower. a two-year field experiment was conducted in a semi-arid region in iran in 2007 and 2008. the experiment was a split plot in a randomized complete block d...

in order to investigate the effect of different levels of biological fertilizers on potato performance (cv. marfona), an experiment was carried out as strip plot based on rcb design with 3 replications in 2011 at isfahan. treatments included nitrocara at 4 levels (0: control, 220, 330 and 440 ml.ha-1) as a first factor and nitroxin+ phosphate at 4 levels (0+0: control, 20+100, 30+150 and 50+200...

In order to investigate the effect of urea, Azocompost and cutting on growth characteristics of Oregano, a factorial split-plot experiment was conducted based on randomized complete block design with three replications at Yazd and Mashhad, Iran, during 2012-2013 growing season. Four urea levels and four Azocompost levels (to provide 0, 40, 80 and 120 kg N.ha-1 each) for Yazd location )0, 43.5, ...

In this study, the effects of nitrogen fertilizer and plant growth regulator (ethephon) application on leaf chlorophyl, stem height and diameter, stalk yield, total sugar and bioethanol of sweet sorghum were determined. Four nitrogen treatments 0, 100, 200 and 300 Kg Urea ha-1 and four ethephon concentrations 0, 800, 1000, and 1200 ppm were applied on sweet sorghum in a split plot on randomized...

salicylic acid (sa) is a phyto-hormone that regulates physiological and biological processes in plants and can be used to improve plant growth under different environmental conditions, including water stress. thus, a field experiment as split plot factorial based on randomized complete blocks design with three replications was conducted in 2014 to investigate the effects of fertilizer and salic...