in this research for study the effects of nitrogen fertilizer on yield and yield components of current rice cultivars was an experiment as factorial in rcbd with three replications where conducted during 2009 year in two locations (rice research institute, rasht, and rudsar, east of guilan). factors were cultivars (khazar, ali kazemi and hashemi), and nitrogen fertilizer levels (0, 30, 60, and ...

Field experiments were conducted to evaluate plant population and N-fertilizer effects on yield and yield components of maize (Zea mays L.). Three levels of plant populations (53000, 66000, and 800,000 plants ha⁻¹ corresponding to spacings of 75 × 25, 60 × 25, and 50 × 25 cm) and 4 doses of N (100, 140, 180, and 220 kg ha⁻¹) were the treatment variables. Results revealed that plant growth, ligh...

Assistant Professor of Botany, Duke University, Durham, N.C. 27706; and Research Assistant, Department of Biological Sciences, University of California, Santa Barbara, CA 93106 Abstract: Precipitation and dry fallout were collected over a 2-year period at a remote site in the Santa Ynez Mountains, Santa Barbara County, California, USA and analyzed for nutrient content. Mean annual depositions o...

Artemisia annua is used as a source of artemisinin, a potent therapeutic agent used for the treatment of infectious diseases, chiefly malaria. However, the low concentration (from 0.01 to 1.4% of dried leaf matter) of artemisinin in the plant obtained with the traditional cropping system makes it a relatively expensive drug, especially in developing countries. Considering that artemisinin and s...

Limited information is available on water and nitrogen (N) management of sugarcane (Saccharum officinarum L.) in Khuzestan, southwestern Iran, where this crop is currently and extensively grown under heavy irrigation and N fertilization. Therefore, a field experiment was conducted from September 2000 to March 2002 at the Research Department of Karoon Agro-industry in Khuzestan to determine the ...

A 3- years (2015, 2016 and 2017) field study was carried out at National Wheat Research Program, Bhirahawa, Rupandehi, Nepal to evaluate the influence of crop residues and nitrogen levels on rice. The experiment was conducted in split plot design with three replications. Main plots were two crop residue levels (with crop residues of 30 cm wheat stubble and without crop residues) and sub plots c...

We reconstructed the historical trends in atmospheric deposition of nitrogen to Cape Cod, Massachusetts, from 1910 to 1995 by compiling data from literature sources, and adjusting the data for geographical and methodological di!erences. The reconstructed data suggest that NO 3 -N wet deposition to this region increased from a low of 0.9 kg N ha~1 yr~1 in 1925 to a high of approximately 4 kg N h...

An experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh during boro season of 2014 to evaluate the effect of deep placement of nitrogen (N) fertilizers on N use efficiency and yield of BRRI dhan29 under flooded condition. The soil was silt loam in texture having pH 6.27, organic matter content 1.95%, total N 0.136%, available P 3.16 ppm...

limited information is available on water and nitrogen (n) management of sugarcane (saccharum officinarum l.) in khuzestan, southwestern iran, where this crop is currently and extensively grown under heavy irrigation and n fertilization. therefore, a field experiment was conducted from september 2000 to march 2002 at the research department of karoon agro-industry in khuzestan to determine the ...