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...

Plant leaf nutrient concentrations and resorption are sensitive to fertilization, yet their co-responses under different nutrient-limited conditions have not been well studied. We conducted a meta-analysis from global dataset of 43 reports, including 130 observations studies with plant nitrogen (N) or phosphorus (P) efficiency (NRE) (PRE), in response fertilization divided by the thresholds N:P...

Fertilizer amendments can impact weed populations in a variety of ways. This study evaluated the effects of 12 year-long applications of different fertilization systems on size and composition of the weed seed bank in a conventionally managed maize monoculture field. Fertilization systems included all factorial combinations of two dairy cattle slurry rates, three vegetable, fruit and garden was...

Disposal of poultry litter, a widely available organic manure in the southeastern USA because of a largescale poultry industry, is a major concern because of its contamination in surfaceand groundwater through N leaching and P runoff. Application of poultry litter in no-tilled intensive cropping system could increase soil C and N sequestration compared with the conventional-tilled system with i...

a three-year field experiment was conducted under conditions of luvic chernozem soil. diversified nitrogen fertilization with 0, 60, 120, and 180 kg n ha-1, and microbial preparations improving soil properties were applied to potatoes, cv. ‘satina’, cultivation. n–no3 concentration in the soil profile (0–0.9 m) in autumn after potato harvesting fluctuated from 28 kg n ha-1 in the n0 treatment t...

Background: Chemical activation is the most frequently method for artificial oocyte activation, resultant in high fertilization rates. The aim of this prospective randomized controlled study is evaluating the effect of calcium ionophore on fertilization and pregnancy rate in infertile men suffering from teratoospermia. Materials and Methods: 38 women with teratoospermic partner were divided int...

The expansion of soybean (Glycine max (L.) Merr) acreage, increasing yields, and recent nitrogen (N) fertilization recommendations could have a major effect on the contribution of biological N fixation (BNF) in soybeans to reactive nitrogen (Nr) in the environment. We used N natural abundance to separate fixed N into grain, aboveground vegetative biomass, and roots along a 9-point N-fertilizer ...

Nitrogen (N) addition typically increases overall plant growth, but the nature of this response depends upon patterns of plant nitrogen allocation that vary throughout the growing season and depend upon canopy position. In this study seasonal variations in leaf traits were investigated across a canopy profile in Miscanthus (Miscanthus 9 giganteus) under two N treatments (0 and 224 kg ha ) to de...

We examined 6I3C and 6 " ~ in needle (current and 1-year-old) and soil samples collected on two occasions (July and September 1999) from a 15-year-old loblolly pine (Pinus taeda L.) stand in an irrigation and fertilization experiment to investigate whether these treatments leave specific isotope signals in the samples and thus to infer the effects of treatments on C and N cycling. Irrespective ...

Human activities have greatly altered global carbon (C) and Nitrogen (N) cycling. In fact, atmospheric concentrations of carbon dioxide (CO2) have increased 40% over the last century and the amount of N cycling in the biosphere has more than doubled. In an effort to understand how plants will respond to continued global CO2 fertilization, long-term free-air CO2 enrichment experiments have been ...