to assess the interaction effects of weeds, sowing rate, and n splitting on dryland wheat yield, field experiments were conducted in two years (2007 and 2009) at the college of agriculture in shiraz university. the treatments were replicated four times and analyzed as a split- split plot in a randomized complete block. the weedy and weed free were treated as the main plots, the wheat sowing rat...

A greenhouse study was conducted to determine the effects of soil type on the response of ‘Russell’ bermudagrass [Cynodon dactylon (L.) Pers.] to broiler litter applications. Soils included Leeper clay loam (fine, smectitic, nonacid, thermic Vertic Epiaquept), Marietta silt loam (fine-silty, mixed, active, thermic Oxyaquic Fraglossudalf), and Ruston sandy loam (fine-loamy, siliceous, semiactive...

Dynamics of cropland soil organic carbon (SOC) in response to different management practices and environmental conditions across North China Plain (NCP) were studied using a modeling approach. We identified the key variables driving SOC changes at a high spatial resolution (10 km × 10 km) and long time scale (90 years). The model used future climatic data from the FGOALS model based on four fut...

Nitrogen (N) pollution induced by irrigated agriculture is a significant environmental problem. The main N inputs and outputs were measured or estimated in the semi-arid La Violada irrigation district (Spain). Data on two periods (1995-98 and 2006-08) were compared and related to observed changes during the decade in cropping patterns and N fertilization and irrigation management. N fertilizati...

in order to study the effects of plant density and nitrogen rates on yield, nitrate and protein of silage maize (ksc 704) in shahrekord area, an experiment was conducted during 2007 growing season at the agricultural research farm of shahrekord university. the experimental design of the experiment was randomized complete blocks with factorial arrangement with four replications. treatment consis...

Wheat (Triticum aestivum L.) was planted as winter crop using raised bed and conventional planting system with four N levels at Regional Wheat Research Station, Rajshahi (latitude 28°75′ N and longitude 92°58′ E), during November to March in 2002 and 2003 to study N content in grain and straw, uptake of total nitrogen, N use efficiency, fertilizer recovery percentage and grain yield. The highes...

In order to study the effect of irrigation interval, N fertilizer and superabsorbent on yield and qualitative traits of sesame (Sesamum indicum L.), a split-split-plot experiment was coducted in a farm in Khusf of Birjand, Iran in 2009 on the basis of a Randomized Complete Block Design. The main plot was devoted to irrigation interval at three levels of 6, 12 and 18 days, the sub-plot was devot...

Intensive agriculture and increased N-fertilizer use have contributed to elevated emissions of the greenhouse gases, CO2, CH4, and N2O. In this study, the exchange of the greenhouse gases, CO2, N2O, and CH4, between a Quincy fine sand (mixed, mesic Xeric Torripsamments) soil and atmosphere was measured in a sweet corn (Zea mays L.) sweet corn potato (Solanum tuberosum L.) rotation during the 20...

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...