introduction: soil fertility management is a key factor in achieving sustainable agriculture. use of organic fertilizers is one of the methods that without environmental harmful effects with improvement of chemical and biological conditions increases soil fertility. nitroxin contains a collection of the best strains of nitrogen fixation bacteria of the genus azospirillum and azotobacter. these ...

Field experiments are described involving nitrogen fertilizer in wheat field to research its effect on microbial quantity and enzyme activity. The results showed that 250 kg N hm applied in wheat field (1) can increase bacteria, fungi, actinomycetes quantity by 39.9%, 56.7% and 70.5% compare to 0 kg N hm. (2) Similarly, the activities of soil urease, catalase and FDA expressed 60.8%, 18.3% and ...

abstract fertilizer use efficiency (fue) is one way of improving the fertilizer management in agriculture. in this study, spinach (spinacea oleracea) was used as a case study vegetable to determine its nitrogen use efficiency in varamin, iran. an experiment was conducted using split plot design with three replications. treatments included of five levels of n as 0, 150, 200, 250 and 300 kg ha-1 ...

The purpose of this study is to investigate the interactions between irrigation and fertilizer treatments on soil NO3 (-)-N content and vertical distribution under drip fertigation in greenhouse tomatoes. Randomized block design with three replications and the treatments consisting of three levels of irrigation and three levels of N fertilizer were used. Three irrigation levels were W1 (100%  E...

this research was conducted on determination of better planting distance and better amount of nitrogen and phosphorus for hybrid rice (bahar 1). planting distance were used in this experiment, include 30×15, 30×20 and 30×25 cm as main factor. and also nitrogen fertilizer was used, include four levels, 65, 95, 125 and 155 k/ha and phosphorus fertilizer used include tow levels, 50 and 100 k/ha as...

Excessive use of animal manure on agricultural lands can impact the quality of surface and groundwater resources. A three–year study (1998–2000) was conducted on nine 0.4–ha plots and on six 2.1–m 2 lysimeters to investigate the effect of two nitrogen (N) application rates from laying hen manure and one N application rate from urea ammonium nitrate (UAN) fertilizer on surface and groundwater qu...