to evaluate the effects of phosphate solubilizing bacteria and chemical phosphorous fertilizer on turnip (brassica rapa) forage yield under limited irrigation regimes, a field experiment was conducted in research farm of college of agriculture and natural resources, university of tehran, in karaj/iran during 2009 growing season. the experimental treatments were arranged as split plots. five lev...

I develop a two-period stochastic dynamic programming model to explain the interaction between fertilizer use and off-farm labor supply. I use a well-known sample of farmers in the semi-arid tropics of India to test the model. I find that fertilizer use responds strongly to wages in the village labor market and that irrigation raises fertilizer use, while larger farmers use less fertilizer than...

in order to determine the effects of applied phosphate bio-fertilizer on yield and morphological traits of wheat, a research was conducted in sari agricultural sciences and natural resources university during 2008-2010. a factorial experiment was performed based on randomized complete block design with four replications. the first factor consists of two levels of phosphate bio-fertilizer (0 and...

To evaluate the process of nitrate accumulation and leaching in surface and ground water, we conducted simulated rainfall experiments. The experiments were performed in areas of 5.3 m2 with bare slopes of 3° that were treated with two nitrogen fertilizer inputs, high (22.5 g/m2 NH4NO3) and control (no fertilizer), and subjected to 2 hours of rainfall, with. From the 1st to the 7th experiments, ...

A 2-year study was done to compare the effects of nitrogen (N) fertigation and granular fertilizer application on growth and availability of soil N during establishment of highbush blueberry (Vaccinium corymbosum L. "Bluecrop"). Treatments included four methods of N application (weekly fertigation, split fertigation, and two non-fertigated controls) and four levels of N fertilizer (0, 50, 100, ...

A study was conducted to determine the efficacy of applying ground magnesium limestone (GML) or ground basalt in combination with bio-fertilizer to sustain rice production on an acid sulfate soil in Malaysia. Soils from Kelantan Plains, Malaysia, were treated with GML, ground basalt, bio-fertilizer, GML + bio-fertilizer, and ground basalt + bio-fertilizer (4 t ha 1 each). Results showed that so...

In east-central Illinois, fertilizer sales during the past 20 yr suggest that approximately half of the fertilizer nitrogen (N) applied to corn ( L.) occurs in the fall; however, fall fertilizer N sales were greatly reduced in 2009 as wet soil conditions restricted fall fieldwork, including fertilizer N applications. In 2010, we observed unusually low flow-weighted nitrate concentrations (appro...

In order to improve the use efficiency of a cover crop, hairy vetch (Vicia villosa R., HV), and supplemental chemical N fertilizer, N release and uptake patterns from HV, fast-release N fertilizer (Fast), and slow-release N fertilizer (Slow) in fresh market tomato (Solanum lycopersicum L.) production were investigated using the 15N-labeling method. In the incubation of soil-added N at two mix r...

Agricultural phosphorus (P) use is intricately linked to food security and water quality. Globalization of agricultural systems and changing diets clearly alter these relationships, yet their specific influence on non-renewable P reserves is less certain. We assessed P fertilizer used for production of food crops, livestock and biofuels in the US agricultural system, explicitly comparing the do...