Intensive agricultural systems are largely responsible for the increase in global reactive nitrogen compounds, which are associated with significant environmental impacts. The nitrogen cycle in agricultural systems is complex and highly variable, which complicates characterization in environmental assessments. Appropriately representing nitrogen inputs into an ecosystem is essential to better u...

In order to study the effect of nitrogen rate and plant density on morphological traits and essential oil and fruit yield of coriander, a split-plot experiment was carried out in research field of Islamic Azad University, Birjand Branch, Birjand, Iran in 2010 based on a randomized complete block design with three replications. The main plots were nitrogen rates at four levels (0, 40, 80 and 120...

An assessment of the nitrogen fertilization efficiency should not only include quantitativeand qualitative yield changes, but also an analysis of formation some indicators such as: Nharvest index (NHI), N use efficiency (NUE), N utilization efficiency (NUtE), N agronomicefficiency (NAE), N physiological efficiency (NPE) and N apparent recovery fraction (NRF).The objective of the study was the e...

A 2-year field study was carried out to find out the effect of three macro nutrients NPK on the severity of Alternaria leaf blight and yield of mustard. Nitrogen @ 80, 100, 120, 140, and 160, phosphorus @ 15, 30, and 45, and potassium @ 30, 60, and 90 kg/ha were applied. Among the nutrients, 120-3060 kg NPK/ha was considered as recommended dose on the basis of soil test. Fertilizer dose 120-30-...

in order to evaluate the effect of different sources and rates of nitrogen the growth and biomass production of purslane, a randomized complete block design was conducted with three replications at the agricultural research farm of shahrekord university in 2012. fertilization treatments were consisted of control (no n amendment), 30 and 90 kg n ha-1in the form of urea fertilizer, 30 and 90 kg n...

Nitrogen fertilizer applications, for maximum fertilizer efficiencies and crop yields, should be based on the N required by the crop during its various growth stages. The objectives of this paper were to identify the N requirements of the potato plant (Solarium tuberosurn L.) during growth and to evaluate selected soil and plant tissue tests as indicators of the plant's N status. Growth analysi...