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...

This study was conducted at the Agricultural Research Station, King Abdulaziz University at Hada El-Sham during 2007 and 2008 seasons to improve the seed yield of sesame (Sesamum indicum L.) in the Makkah Region, Saudi Arabia. Split plot design with four replications was used in this study. Main plot treatments were four nitrogen rates (0, 100, 150 and 200 kg N/ha) and the sub plot treatments w...

Root crops are an important staple food in the Pacific region. Yields are generally low and inorganic fertilizers are deemed an option to increase root crop production. The effects of inorganic N fertilizers on upland taro (Colocasia esculenta (L.) Schott) and sweet potato (Ipomoea batatas (L.) Lam.) were quantified with the aim to investigate relationships between inherent soil fertility, N up...

Given the finite nature of global phosphorus (P) resources, there is an increasing concern about balancing agronomic and environmental impacts from P usage on dairy farms. Data from a 3-year (2009-2011) survey were used to assess farm-gate P balances and P use efficiency (PUE) on 21 intensive grass-based dairy farms operating under the good agricultural practice (GAP) regulations in Ireland. Me...

to evaluate the effect of time and level of nitrogen application on quantity and quality of two carrot varieties, an experiment was carried out in the framework of a 4×3×2 factorial and based upon a randomized complete block design of three replications. the levels of 25, 50, 75 and 100 kg / ha of nitrogen fertilizer were investigated within 3 applied times, namely: simultaneous with bed prepar...

Wheat is the most widely cultivated food crop in the world, which provides nutrition to most of the world population and is well adapted to a wide range of environmental conditions. Timely and efficient rates of nitrogen (N) application are vital for increasing wheat grain yield and protein content, and maintaining environmental sustainability. The goal of this study was to investigate the effe...

To quantify the effect of a reduction in nitrogen fertilizer on grass intake and animal performance, four zero-grazing experiments were carried out, two in spring /early summer and two in late summer. Grass was fertilized at three levels of N fertilizer, 450, 300 and 150 kg/ha per year and harvested daily at dry matter yields between 1500 and 2000 kg/ha. Grass was fed ad libitum to three groups...

A study was conducted to compare secondary metabolites and antioxidant activity of Labisia pumila Benth (Kacip Fatimah) in response to two sources of fertilizer [i.e., organic (chicken dung; 10% N:10% P₂O₅:10% K₂O) and inorganic fertilizer (NPK green; 15% N, 15% P₂O₅, 15% K₂O)] under different N rates of 0, 90, 180 and 270 kg N/ha. The experiment was arranged in a randomized complete block desi...

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...