abstract improving nitrogen use efficiency (nue) is an important objective of the agroecosystem management. a field experiment was conducted to study the effect of different competition patterns on nitrogen balance in the wheat agroecosystem. experimental design was split–plot based on randomized complete blocks with four replications. the main plots consisted of different nitrogen rates (i.e. ...

the effect of nitrogen (n) levels on n uptake by high weed densities at early growth stages of corn (zea mays l., cv. double cross 370) was investigated for two years (2008-2009) at the agricultural research station of shiraz university. the experiment was arranged in a split-plot arrangement in the randomized complete blocks design with three replications. two levels of weed control (weedy and...

in order to investigate the effects of different levels of nitrogen rate on yield and seed yield components of wheat cultivars, an experiment was conducted on araghi mahalleh (gorogan) research farm in 2008. treatments, nitrogen in the form of urea (0, 90, 180 and 270 kg/ha) and cultivars (tajan, falat and n81-18) were arranged as factorial based on randomized complete block design with four re...

in order to evaluate the yield and nitrogen use efficiency of corn and cotton intercropping under different levels of nitrogen, an experiment was conducted as a factorial arrangement based on completely randomized block design with three replications. the experimental treatments were nitrogen fertilizers in four levels (0, 50, 100 and 150 kg ha-1) and planting pattern in three levels (maize sol...

in order to evaluate efficiency of nitrogen fertilizers consumption in a sugar beet monogerm hybrid variety of zarghan, a field experiment was conducted in a loamy soil during 2007 in the research farm of sugar beet seed institute located in karaj. five levels of nitrogen fertilizers including 0 (check), 120, 160, 200 and 240 kg/ha of net nitrogen from urea fertilizer (46 percent of pure nitrog...

in order to evaluate different sources and rates of nitrogen on dry matter yield, concentration and uptake of primary macronutrients (nitrogen, phosphorous and potassium) in forage sorghum (hybrid of speedfeed), three levels of nitrogen (80, 160 and 240 kg n ha-1) from three n sources (urea fertilizer, cattle manure and equal combination of urea fertilizer + cattle manure) and the control (no f...

in order to effects of fertilizer source and intercropping ratios on macronutrients concentration and uptake of fenugreek and black cumin, a factorial experiment was conducted as randomized complete block design with three replications at shahrekord university research farm in 2013. sole cropping of fenugreek (f) and sole cropping of black cumin (b) and three intercropping ratios (f:b 2:1, f:b ...

in order to study the effects of simultaneous application of znso4 and biological fertilizer, azotobacter chroococcum and azospirillum brasilense, on grain yield and nitrogen uptake efficiency in rapeseed (brassica napus l.), cv. hyola308, a field experiment was conducted as split plot factorial based on randomized complete block design at research field of faculty of agricultural sciences, uni...

in the present study, the root vigor and kinetic characteristics of nitrogen absorption in potato cultivars was investigated through sand cultivation and pot tests with nutrient solution. four cultivars of potatoes, namely, feiwuruita, yunshu301, liangshu97, and chuanyu56 were grown in nutrient solution matrix cultures. the result showed that: (1) nitrogen uptake rates differed significantly am...