to study the effects of biofertilizers in their different levels of nitrogen (n) and phosphorus (p) on yield related parameters of barley (sahra cultivar), a split plot experiment based upon a randomized complete block design of three replications was conducted. main plots consisted of: nitrogen at three levels (0, 50 and 100 kg n ha-1 as urea), while sub plots were: phosphorus at two levels (0...

the aim of this study was to determine the effects of ensiling and using of fertilizers nitrogen and phosphorus on chemical composition and ruminal dm degradability of safflower plant (carthamustinctorius l.). the safflower plant was cultivated at december 2009, and harvested at june 2010 in flowering stage, chopped to 3-5 cm particles and then ensiled in the laboratory silos for 60 days. the e...

The ecological problems caused by dry and wet deposition of atmospheric nitrogen have been widespread concern in the world. In this study, wet and dry atmospheric depositions were monitored in plant growing season in the coastal zone of the Yellow River Delta (YRD) using automatic sampling equipment. The results showed that SO4 (2-) and Na(+) were the predominant anion and cation, respectively,...

Temporal changes in nitrogen concentrations and stream discharge, as well as sediment and nitrogen losses from erosion plots with different land uses, were studied in an agricultural watershed in the Taihu Lake area in eastern China. The highest overland runoff loads and nitrogen losses were measured under the upland at a convergent footslope. Much higher runoff, sediment and nitrogen losses we...

In the sub-tropics, water and nitrogen are the most important factors limiting the grain yield of maize. The effect of nitrogen (N) rates and drought stress at different growth stages of maize were investigated. Nitrogen treatments consisted of 100, 150, and 200  kgN.ha-1 from the urea source while water stress treatments were composed of irrigation-off since the early 10-leaf stage to emergenc...

In order to study the effect of water deficit stress and different nitrogen levels on flower yield, yield components and water use efficiency of Calendula officinalis L., an experiment was conducted as split plot based on randomized complete block design with three replications, at research field of Islamic Azad University, Birjand branch in 2009. In this experiment, irrigation treatments (irri...

This study examined the effects of various levels of nitrogen inputs (optimal, insufficient and excessive) and water inputs (optimal, low drought and high drought) to tomato plants (Solanum lycopersicum) on survival and development of an invasive tomato leafminer, Tuta absoluta (Meytick) (Lepidoptera: Gelechiidae). Plant growth i.e. plant height and the number of nodes declined under insufficie...

Nitrogen isotope analysis is now commonly used to investigate the diets, and to a lesser extent, the environments of ancient populations. These studies assume that mammals are predictably enriched in N over their food, and concomitantly, that N becomes increasingly concentrated as one moves up the food chain. The literature commonly states that this N-enrichment of mammalian tissues is due to p...

A split plot 3 by 4 experiment was designed to examine the impact of 15-week variable levels of nitrogen fertilization (0, 90, 180 and 270 kg N/ha) on the characteristics of total flavonoids (TF), total phenolics (TP), total non structurable carbohydrate (TNC), net assimilation rate, leaf chlorophyll content, carbon to nitrogen ratio (C/N), phenyl alanine lyase activity (PAL) and protein conten...

Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha(-1) yr(-1)) in order to assess the potential risk facing this orchid given impendi...