a field study was conducted to determine the integration of split n fertilization and herbicide application on weed management and wheat (triticum aestivum l.) yield in shiraz, iran, in 2005/2006 and 2006/2007 growing seasons. the experimental design was split plot with four replications. main factors consisted of n timing and splitting, and sub plots included iodosulfuron–methyl–sodium plus me...

crop rotation affect on crop nitrogen uptake and nitrogen use efficiency (nue). crop rotations with high nue decrease energy use and increase level of sustainability in agro ecosystems. the objectives of this research were to determine the suitable double cropping system for enhancing nue and evaluate the effects of crop rotation, n fertilizer rate and return of crop residue on nue. this study ...

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...

abstract- crop residue is applied to amend soil properties and increase crop yield. in this study, the effects of rapeseed residues and different rates of nitrogen on grain yield and yield components of sunflower and weed dry matter were investigated. the experiment was conducted at the experimental farm of college of agriculture, shiraz university, located at badjgah, shiraz, iran in 2007-2008...

in order to evaluate the effects of ethephon and nitrogen fertilizer on sweet sorghum cv. sofra, an experiment was conducted as split plot on a randomized complete block design with three replications at agricultural research station of isfahan university (isfahan, iran). experiment was conducted with four nitrogen levels (0, 100, 200 and 300 kg urea ha-1 from urea with 0, 46, 92 and 138 kg nit...

BACKGROUND: Wheat produces more than 50 percent of requirements protein and calorie for human nutrition in Iran. Management of nitrogen fertilizing is important to increasing wheat production. So, among chemical fertilizer a high correlation reported between nitrogen and yield. Also to improve physical, chemical and biological properties of soil, organic fertilizer such as verm...