Repeated fertilizer applications to cultivated soils may alter the composition and activities of microbial communities in terrestrial agro-ecosystems. In this study, we investigated the effects of different long term fertilization practices (control (CK), three levels of mineral fertilizer (N1P1K1, N2P2K2, and N3P3K3), and organic manure (OM)) on soil environmental variables and microbial commu...

Nonpoint-source pollution of fresh waters by P is a concern because it contributes to accelerated eutrophication. Given the state of the science concerning agricultural P transport, a simple tool to quantify annual, field-scale P loss is a realistic goal. We developed new methods to predict annual dissolved P loss in runoff from surface-applied manures and fertilizers and validated the methods ...

monly used instruments is a Minolta SPAD (soil plant analysis development) meter. The SPAD meter measures the difference in light absorption at 430 and 750 nm (Wood et al., 1992). The former is the transmittance peak for chlorophyl ‘a’ and ‘b’, and the latter is in the near-infrared region. The instrument converts the difference in light absorption at these two wavelengths into a numerical SPAD...

to study the effect of different fertilization systems on forage quality and secondary metabolites ofmedicinal forage in additive intercropping of alfalfa and fennel an experiment was conducted as split plotbased on randomized complete block design with three replications at college of agriculture, shaheduniversity in tehran, 2011. the main plots were allocated to different levels biofertilizer...

Fertilizer with different ratios of nitrogen (N) to phosphorus (P) can influence crop plant performance and defense against herbivores. Spodoptera exigua is an important agricultural pest that has caused serious economic loss, especially in recent decades. In the present study, we explored effects of different intensities and durations of S. exigua herbivory on host plant biomass and on S. exig...

Large quantities of phosphate present in wastewater is one of the main causes of eutrophication that negatively affects many natural water bodies, both fresh water and marine. It is desirable that water treatment facilities remove phosphorus from the wastewater before they are returned to the environment. Total removal or at least a significant reduction of phosphorus is obligatory, if not alwa...

In order to study the effects of nitrogen (N), phosphorus (P) and potassium (K) on the yield, the appearance eligibility ratio and the contents of total glucosinolates and glucoraphanin of cauliflower, the 311-A optimization regression design was used to conduct field experiments of N, P, K fertilizer treatments using winter cauliflower variety ‘‘HB16’’. The models of the balanced application f...

In this study, poultry manure compost and organic fertilizer were added to soils derived from basalt, granite, and river alluvial deposits for use as soil parent materials. Following incubation periods of 30 or 60 days at 25 °C, the physical and chemical properties and adsorption characteristics of the soils were studied. The results indicated that the application of poultry manure compost or o...

Increased phosphorus (P) fertilizer use and livestock production has fundamentally altered the global P cycle. We calculated spatially explicit P balances for cropland soils at 0.5° resolution based on the principal agronomic P inputs and outputs associated with production of 123 crops globally for the year 2000. Although agronomic inputs of P fertilizer (14.2 Tg of P·y(-1)) and manure (9.6 Tg ...