in order to investigate the effects of soil chemical characteristics on weed species diversity in eastern mashhad region wheat (triticum aestivum l.) fields, an investigation was held in the year 2009. wheat fields were classified based on the acreage from 3-5, 5-10 and higher than 10 ha. five random soil samples were taken using a 5 cm diameter auger from the soil of each experimental field an...

introduction: today, production of organic farming and gardening is rising. the use of organic fertilizers such as animal manure has a long history. in recent years, the use of fertilizers and manure for providing the nutritional needs of plants, improve soil physical and chemical structure and reduce the environmental issues have been observed. animal manures can increase soil organic matter a...

background and objectives: soybean is one of the plants that need large amounts of nitrogen for grain yield production. todays bio-fertilizers are considered as a best replacement for chemical nitrogen to increase soil fertility and sustained agricultural production. meanwhile, the use of soybean symbiotic bacteria and nitroxin, which contain the most effective nitrogen-fixing bacteria of the g...

Plant photosynthate fuels carbon-limited microbial growth and activity, resulting in increased rhizosphere nitrogen (N) mineralization. Most soil organic nitrogen is macromolecular (chitin, protein, nucleotides); enzymatic depolymerization is likely rate limiting for plant nitrogen accumulation. Analyzing Avena (wild oat) planted in microcosms containing sieved field soil, we observed increased...

Voles are well-known crop pests, especially when peak populations are present, but their role in soil fertility and impacts on agricultural sustainability are not well understood. Five months after the abrupt disappearance of a peak in a gray-tailed vole (Microtus canicaudus) population, we examined burrow structure, determined concentrations of trace elements, carbon and nitrogen in the soil i...

The main objective of this paper is to check the soil fertility and salinity status. For this purpose, a total of 3325 soil samples, collected from all tehsils of Muzffargarh district (from tehsil Muzaffargarh, Jatoi, Kot Addu and Ali Pur), were tested in the Soil and Water Testing Laboratory, Cane Development Cell, Fatima Sugar Mills, Muzaffargarh, Pakistan from 2012 to 2014. Samples were anal...

The study of free-living nitrogen-fixing organisms in bulk soil is hampered by the great diversity of soil microbial communities and the difficulty of relating nitrogen fixation activities to individual members of the diazotroph populations. We developed a molecular method that allows analysis of nifH mRNA expression in soil in parallel with determinations of nitrogen-fixing activity and bacter...

introduction soil salinity is a major limiting factor in agricultural development within iran. nitrogen is the most important nutrient that its uptake is limited over other elements under saline conditions due to decrease in the permeability of plant roots, soil microbial activity and mineralization of organic compounds and nitrate uptake by high concentrations of chloride anions in the root zo...

in order to evaluate efficiency of nitrogen fertilizers consumption in a sugar beet monogerm hybrid variety of zarghan, a field experiment was conducted in a loamy soil during 2007 in the research farm of sugar beet seed institute located in karaj. five levels of nitrogen fertilizers including 0 (check), 120, 160, 200 and 240 kg/ha of net nitrogen from urea fertilizer (46 percent of pure nitrog...

abstract in order to investigate the effects of nitrogen fertilizer levels on the yield and quality of potato, (solanum tuberosum l.) a field experiment was conducted based on randomized complete blocks design with 3 replications in the research field of the college of agriculture, ferdowsi university of mashhad. nitrogen topdress fertilizer was applied in two levels of 100 and 150 kgn.ha-1 and...