introduction: nitrogen is an essential element forplants and in combination withelements such as carbon, oxygen, hydrogen and sulfur results ineven more valuable materials such as amino acids, nucleic acids, alkaloids. hibiscus tea (hibiscus sabdariffa ) from malvaceaefamily is known by different names in different parts of the world. in iran it is calledthe maki tea, tea meccaorred tea.as an i...

the experimental was split plot in a randomized complete block design with three replications. in this experiment, different levels of nitrogen in the main plots included four levels (0, 50, 100 and 150 n) kg.ha-1 urea and wheat varieties, including cultivars, sepahan and sw were placed in the subplots. results showed that nitrogen fertilizer and cultivar were significant effects on maximum lig...

optimum uses of water and nitrogen resources are the most important factors in agricultural systems due to limitations of agricultural inputs especially water. in order to investigate the effect of different levels of nitrogen fertilizer and irrigation on efficiency and productivity of water consumption in three crop (sugar beet, corn and sesame) an experiment was carried out as strip split plo...

the objective of this study was to evaluate the effect of different levels of irrigation and nitrogen fertilizer on nitrate movement, yield, and water use efficiency (wp) of corn in no-till planting method. the research was conducted in two years as a randomized complete block design arranged in a split block treatment design with three replicates in the safiabad agricultural research center. i...

Nitrogen management practices have an effect on crop yields but they can also have a negative impact on the environment. Practices such as banding fertilizer and/or split-applying total nitrogen needs per acre offer a more efficient use of nitrogen by significantly reducing nitrate leaching potential. Heavy rains occurring when plants are small and nitrogen demands are low can also increase nit...

the present research was carried out with the aim of site-specific nitrogen fertilizer management, through aster imagery. a 23 ha corn field in pakdasht town in southern tehran province constituted the research area. plant sampling was carried out simultaneous with the passing by of the satellite sensor over, throughout the farm. a total of 53 pixels were selected through systematic randomized ...

In order to investigate the effects of nitrogen fertilizer levels and intercropping ratios on yield and other morphological traits of two crops, field experiments were conducted during two years (2010-2011) in the research field of the school of Agriculture, Shiraz University, Shiraz, Iran. The study was carried out in a factorial experiment laid out based on a completely randomized block desig...

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 ...