Effects of Aeration,Molasses, Kelp,Compost Type,And Carrot Juice on the Growth of Escherichia Coli in Compost Teas

Growth of a nonpathogenic E. coli strain (K12- MG1655, ATCC 700926) in aerated and nonaerated compost teas containing molasses, kelp and carrot juice was examined. Teas were prepared using four different compost types that had undetectable levels of indigenous E. coli. Three of the composts were produced by turn pile windrow composting method using dairy, swine and horse manure as feedstock, while the fourth, a vermicompost, was produced by feeding separated dairy solids to worms Eisenia feotida. Molasses and kelp enhanced the growth of E. coli in inoculated teas and the E. coli density was positively correlated with nutrient concentrations ranging from 0.1 to 8.0 g/L. Irrespective of the presence of molasses and kelp, E. coli was not detected in noninoculated teas. Even though E. coli is a facultative anaerobe, its growth was significantly higher in nonaerated teas than in aerated teas. Without aeration, dissolved oxygen in teas declined rapidly and fell below 0.1 mg/L within 20 h, whereas continuous aeration at 0.8 L/min maintained an aerobic condition (> 5 mg/L dissolved oxygen) in teas during the 48 h brewing period. The pH values of nonaerated teas were significantly lower than those of aerated teas and were always slightly acidic. E. coli growth in different compost types was significantly different. The density of E. coli was lowest in teas made with vermicompost and highest in teas made with swine manure compost. E. coli proliferations in both aerated and nonaerated swine manure compost teas were inhibited by carrot juice. Carrot juice lowered dissolved oxygen in aerated teas. The total bacterial densities in noninoculated compost teas were not reduced by carrot juice.     

An Enhanced Direct Process Temperature Validation Framework in Composting: Case Study of a Full-Scale Covered Aerated Static Pile

ABSTRACT

To ensure the safety of compost products, the Canadian Council of Ministers of the Environment's compost guidelines specify upper limits for certain pathogenic and indicator microbes, which are presumably achieved by exposing every particle of compost to temperatures ≥55°C for at least three consecutive days. A rugged temperature probe that behaves like a random compost particle was used to investigate whether every compost particle meets the time temperature criterion and to measure sanitation efficacy. An inoculum consisting of Salmonella enterica var. Meleagridis, Escherichia coli K12, and phi-S1 bacteriophage (all at levels of ～1 × 10⁶ CFU/PFU mL^?1) was added into 17 probes. The probes were randomly introduced into a covered, aerated static pile along with 17 probes that only monitored the temperature. After 56 days of composting, with one pile turn the probes were recovered. Organism levels were determined via culture-based methods. Before turning, 80% of the randomly introduced probes satisfied the time-temperature criterion. After turning, this number increased to 87%, demonstrating that turning is somewhat useful for sanitation. The cool zones largely remained mesophilic with the pile turning having minimal impact, which could potentially be an indication that the pile was not turned thoroughly. One of the 17 probes with cryovials reached only 40.2°C, and survival of S. meleagridis (2.5 × 10⁶ CFU ml^?1) was observed. The remaining probes with cryovials exceeded 55°C and were pathogen free. It appears that the specified time-temperature conditions are likely adequate. However, more observations are needed before a firm conclusion can be made.     

Evaluation of Compost for Use as a Soil Amendment in Corn and Soybean Production

The purpose of this research project was to 1) evaluate rate of compost application and 2) to compare compost with uncomposted raw material and inorganic fertilizer N application upon maize and soybean growth and productivity, and upon soil characteristics. During the first three years of the study, the source of uncomposted material and compost was food waste and ground newsprint. During years 4 to 9 of the study, the source of uncomposted material and compost was dairy cow manure and wood chips. Application rates in field site 1 were 0, 11.2, 22.4, 33.6 and 44.8 Mg ha^?1 compost, 44.8 Mg ha^?1 uncomposted material and 140 kg ha^?1 fertilizer N (as urea). Application rates in field site 2 were 0, 22.4, 44.8, 67.2 and 134.4 Mg ha^?1 compost, 134.4 Mg ha^?1 uncomposted manure and 180 kg ha^?1 fertilizer N (dry matter basis). The high rates of compost application significantly raised organic matter levels, and available P and K compared to inorganic fertilizer N. Uncomposted manure and increasing compost application rates significantly increased grain yield, number of kernels per plant and plant weight. Composting significantly reduced pathogen indicator bacteria concentrations. The data of this study suggest that on these high organic matter soils 22.4 Mg ha^?1 to 44.8 Mg ha^?1 are optimal compost application rates.     

Compost and Manure Effects on Fertilized Corn Silage Yield and Nitrogen Uptake under Irrigation

Abstract

Dairy manure increases the yields of dry bean (Phaseolus vulgaris L.) and spring wheat (Triticum aestivum L.) from eroded, furrow‐irrigated soils and may increase corn (Zea mays L.) silage yield from steeper eroded areas under sprinkler irrigation. In a 2‐year field study in southern Idaho on Portneuf silt loam (coarse silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid), the effects of a one‐time, fall application of 29 or 72 Mg ha^?1 of dry manure or 22 or 47 Mg ha^?1 of dry compost on subsequent silage yield and nitrogen (N) uptake from previously eroded, sprinkler‐irrigated hill slopes were evaluated. In October 1999, stockpiled or composted dairy manure was disked to a depth of 0.15 m into plots with slopes from 0.8 to 4.4%. After planting field corn in 2000 and 2001, a low‐pressure, six‐span traveling lateral sprinkler system was utilized to apply water at 28 mm h^?1 in amounts sufficient to satisfy evapotranspiration to 6.4‐×36.6‐m field plots. Yields in 2000 were 27.5 Mg ha^?1, similar among all rates of all amendments and a fertilized control. In 2001, compost applied at oven‐dry rates up to 47 Mg ha^?1 increased yield compared to controls. Silage yield in 2001 increased initially then decreased with increasing manure applications. Where compost or manure was applied, regardless of rate, 2‐year average N uptake was 15% greater than controls. Regardless of treatment or year, yields decreased linearly as soil slope increased.     

NUTRIENT PARTITIONING IN POTTED PEACH (PRUNUS PERSICA L.) TREES SUPPLIED WITH MINERAL AND ORGANIC FERTILIZERS

The aim of the experiment was to evaluate the effect of organic fertilization on nutrient uptake and partitioning in potted peach trees. The study was carried out on 72 peach (Prunus persica L.) plants. The following treatments were compared: 1) unfertilized control, 2) mineral fertilization [713 mg nitrogen (N), 119 mg phosphorus pentoxide (P₂O₅), 476 mg potassium oxide (K₂O) pot^?1], 3) cow manure (119 g dw pot^?1) and 4) compost (119 g dw pot^?1). Compared to the untreated control, plant biomass was improved by supplying cow manure and compost. Potassium concentration in fine roots and leaves was higher in compost treated trees. Leaf concentrations of calcium (Ca) and magnesium (Mg) were decreased by applications of compost and cow manure. Nutrient concentrations in fine roots were always positively correlated with nutrients in coarse roots, only N showed a negative correlation. With the exception of Ca and Mg, macronutrients removed by trees were higher after compost fertilization than in unfertilized controls.     

Microbiological Quality Assessment of Watershed Associated with Animal-Based Agriculture in Santa Catarina, Brazil

Environmental problems many times could evolve when manure-containing pathogens are distributed into an open environment with no effort made to reduce the content of pathogens or limit their movement in the environment. Wind, surface flow, and subsurface flow can all carry enough pathogens to receiving waters to exceed water quality standards. This study was conducted to assess the microbiological quality of water associated with animal-based agriculture in the sub-basin of Pinhal River located in the rural area of Concordia, Santa Catarina, Brazil. Six sampling points representing different agricultural land uses (LU1—dairy cattle; LU2—without animals; LU3—dairy + pigs + poultry + crops; LU4—pigs + poultry + crops; LU5—dairy + pigs + poultry + crops + human; and LU6—dairy+pigs+crops) along the Pinhal River sub-basin (north to south) were sampled biweekly from August 2006 to December 2008. Concentrations of fecal coliforms and Escherichia coli varied significantly (p?≤?0.05) with land use (LU), but there was no interaction effect of LU, season, and time. Water samples from the catchment area of LU1 had the highest concentration of fecal coliforms (4,479?±?597 CFU ml^?1) when compared with other catchment areas. Catchment area associated with LU2 (no animal) had the lowest concentrations of fecal coliforms (39.2?±?5.2 CFU ml^?1). With the exception of LU2 (control site), all the maximum concentrations of E. coli exceeded the single maximum allowable concentration for E. coli (100 CFU ml^?1). When LU1 was compared with other catchment areas (LU3, 50%; LU4, 67%; LU5, 58%; and LU6, 44%), it had the lowest counts (39%) of Salmonella sp. Our results suggest that spatial pattern of bacterial water quality is evident, which can be linked to the different land uses and associated practices (present or absent of animal activities). Therefore, varying responses associated with the different land uses would be critical in identifying the importance of different sources of bacteria in the catchment area and the mechanisms transferring them.     

Effects of fungivorous nematodes on corky root disease of tomato grown in compost-amended soil

Abstract

The effect of fungivorous nematodes, Aphelenchus avenae and Aphelenchoides spp., against corky root disease of tomato caused by Pyrenochaeta lycopersici was investigated. Three different greenhouse trials were conducted using soil naturally infested with P. lycopersici, alone or mixed with four different types of compost consisting of green manure, garden waste and horse manure (20% compost by volume). The fungivorous nematodes were propagated in cultures of the fungus Pochonia bulbillosa and inoculated (3 or 23 nematodes ml^?1 substrate) into the soil and soil-compost mixtures one day after transplanting of tomato seedlings. Greenhouse experiments were terminated after ten weeks and disease was measured from infected roots after harvesting. Aphelenchus avenae significantly reduced the disease severity when added to infested soil without compost in all experiments. Aphelenchoides spp. did not suppress the disease either in the presence or absence of compost. Among the composts tested, only a garden waste compost was found to be suppressive to the disease. Neither A. avenae nor Aphelenchoides spp. improved the suppressive effect of the compost.     

Nutrient Mineralization from Nitrogen- and Phosphorus-Enriched Poultry Manure Compost in an Ultisol

The combination of inorganic fertilizers and compost is a technique aimed at improving crop growth and maintaining soil health. Understanding the rate of nutrient release from enriched compost is important for effective nutrient management. A laboratory incubation study was conducted for 112 days to study the nutrient mineralization pattern of poultry manure compost enriched with inorganic nitrogen (N) and phosphorus (P) fertilizer nutrients in an Ultisol. Compost applied at the rate of either 5 or 10 g kg^?1 was blended with N (50 kg N ha^?1) and P (30 kg P ha^?1). Carbon dioxide evolution and N and P mineralization were measured fortnightly. The bacterial and fungal populations were determined at the mid and end of the experiment. The combination of compost and inorganic N and P increased carbon (C) and P mineralization by 4?8% and 56?289%, respectively, over the application of either compost or inorganic N and P. However, P addition influenced the amount of C mineralized. Inorganic N and P, on the other hand, were better at increasing N mineralization than compost blended with inorganic N and P over a short time. The addition of compost stimulated bacterial and actinomycete populations, while fungal populations were unaffected. Actinomycetes and bacteria had similar and higher relationship trend with C (R² = 0.24) and P (R² = 0.47) mineralization and were key determinants in nutrient mineralization from compost in this Ultisol. Integrating compost with inorganic fertilizers improves nutrient availability through the growth and activities of beneficial microorganisms.     

Effects of Dairy Lot Scrapings and Composted Dairy Manure on Growth,Yield, and Profit Potential Of Double Cropped Vegetables

Government regulations and public pressure have resulted in the use of composting as an alternative waste handling system for dairies. Utilization of locally-produced manures by vegetable production operations may increase crop yields with less conventional fertilizer. Despite its ability to stabilize nutrients and lower manure volume, composting has costs in time and equipment, so some growers prefer using uncomposted manure. Dairy manure compost at 22 (LC), 45 (MC), or 90 (HC) Mg·ha^?1 or uncomposted dairy lot scrapings at 45 Mg·ha^?1 (DL) were tilled into soil before seeding a dryland muskmelon (Cucumis melo L.) crop. All plots, including an unamended control (UC), were fertilized with a total of 23N-14P-0K (kg·ha^?1). After removal of the cantaloupe in late summer, a drip irrigated broccoli (Brassica oleracea var.botrytis Mill.) crop was planted into the identical plots, and sidedressed with 112 kg·ha^?1 N. Muskmelon yields from DL, LC, MC, HC, and UC plots were 9.6, 6.9, 4.1, 9.0, and 2.9 Mg·ha^?1, respectively. Broccoli yields from DL, LC, MC, HC, and UC plots were 4.2, 3.6, 4.4, 4.1, and 2.2 Mg·ha^?1, respectively. All rates of compost or manure increased yields of cantaloupe, and the subsequent broccoli crop. Use of the manure resulted in highest increase in potential net income from sales of muskmelon and broccoli.     

Bioavailability of zinc and lead from a contaminated soil amended with pine bark-goat manure compost

The distribution in soil and plant uptake of zinc (Zn) and lead (Pb) as influenced by pine bark-goat manure (PBG) compost additions were investigated from the soils artificially contaminated with Zn or Pb ions using maize (Zea mays L.) as a test crop. Soils were amended with four rates of pine bark-goat manure compost (0, 50, 100, and 200 tons ha^?1) and four rates (0, 300, 600 and 1200 mg kg^?1) of Zn or Pb. Maize was planted and grown for 42 days. At harvest, plants samples were analyzed for Zn and Pb concentration. Soils samples were analyzed for pH, extractable and diethylene triamine pentaacetic acid (DTPA) extractable Zn and Pb. Extractable Zn and Pb was lower in PBG compost amended soils than in unamended soils and steadily declined with increasing amount of compost applied. The extractable fraction for Zn dropped by 62.2, 65.0 and 44.6% for 300, 600 and 1200 mg Zn kg^?1, respectively when 200 t ha^?1 of PBG compost was applied. Metal uptake by maize plants were directly related to the rate of applied heavy metal ions with greater concentrations of metals ions found where metal ions were added to non-amended soils.     

Nitrogen accumulation in soybean [Glycine max (L.) Merr.] is increased by manure compost application in drained paddy fields as a result of increased soil nitrogen mineralization

The application of manure compost is an effective way to increase soybean [Glycine max (L.) Merr.] yield and nitrogen (N) fertility in drained paddy fields. We investigated changes in soil N mineralization during soybean cultivation using reaction kinetics analysis to determine the contribution of increased N mineralization after manure compost application (at a rate of 0 to 6?kg?m^?2) on N accumulation and seed yield of soybean under drained paddy field conditions. The seed yield and N accumulation decreased markedly in the second and third year of the experiment, but soil N mineralization increased in both years. No decrease in soil N mineralization occurred even after two soybean crops. Soil N availability was not the main cause of decreased soybean yield in the second and third years. The differences in plant aboveground N content between plots with and without manure compost was similar to the increase in N mineralization caused by manure compost application in the second and third years. The application of 6?kg?m^?2 of manure compost increased the amount of ureide-N and nitrate-N in soybean in the third year. Our results suggest that manure compost application increases soil N mineralization and soybean N₂ fixation, resulting in increased N accumulation and seed yield. However, the soybean yield remained less than 300?g?m^?2 in the second and third years (i.e., below the yield in the first year) at all levels of manure compost application due to the remarkable decrease of N accumulation in the second and the third crops.     

Application rate and composting method affect the immediate and residual manure fertilizer value in a maize–rice–rice–maize cropping sequence on a degraded soil in northern Vietnam

A field experiment was carried out in northern Vietnam to investigate the effects of adding different additives [rice (Oriza sativa L.) straw only, or rice straw with added lime, superphosphate (SSP), urea or a mixture of selected microorganism species] on nitrogen (N) losses and nutrient concentrations in manure composts. The composts and fresh manure were applied to a three-crop per year sequence (maize–rice–rice) on a degraded soil (Plinthic Acrisol/Plinthaquult) to investigate the effects of manure type on crop yield, N uptake and fertilizer value. Total N losses during composting with SSP were 20% of initial total N, while with other additives they were 30–35%. With SSP as a compost additive, 65–85% of the initial ammonium-N (NH₄-N) in the manure remained in the compost compared with 25% for microorganisms and 30% for lime. Nitrogen uptake efficiency (NUE) of fresh manure was lower than that of composted manure when applied to maize (Zea mays L.), but higher when applied to rice (Oriza sativa L.). The NUE of compost with SSP was generally higher than that of compost with straw only and lime. The mineral fertilizer equivalent (MFE) of manure types for maize decreased in the order: manure composted with SSP?>?manure composted with straw only and fresh manure?>?manure composted with lime. For rice, the corresponding order was: fresh manure?>?manure composted with SSP/microorganisms/urea?>?manure composted with lime/with straw alone. The MFE was higher when 5 tons manure ha^?1 were applied than when 10 tons manure ha^?1 were applied throughout the crop sequence. The residual effect of composted manures (determined in a fourth crop, with no manure applied) was generally 50% higher than that of fresh manure after one year of manure and compost application. Thus, addition of SSP during composting improved the field fertilizer value of composted pig manure the most.     

Heat Inactivation of E. coli During Manure Composting

Contamination of food and water by microorganisms from animal manure has become an important issue in public health. Escherichia coli O157:H7 is one of several emerging pathogens of concern. In this research, we studied how the self-heating, thermophilic phase of composting influenced laboratory-grown vs. bovine-derived E. coli O157:H7 mortality, specifically the relationship between temperature, time at temperature, and pathogen survival. Composting experiments were conducted in laboratory-scale bioreactors operated in three temperature ranges: 40°C to 50°C, 50°C to 60°C, and greater than 60°C. We measured the effects of temperature and composting time on E. coli O157:H7 mortality. Laboratory-grown E. coli O157:H7, inoculated into the initial compost material, were not detected after approximately 300 degree days of heating. In several experiments where compost temperatures did not rise above 50°C, an initial decline of E. coli O157:H7 with subsequent regrowth was observed. E. coli O157:H7 in compost materials from infected cattle were not detected after approximately 180 degree days of heating. Numbers of total coliform bacteria declined with temperature similarly to those of E. coli O157: H7. The results of this research provide information for reducing or eliminating E. coli O157:H7 in animal wastes.     

Manure as a Source of Antibiotic-Resistant Escherichia coli and Enterococci: a Case Study of a Wisconsin, USA Family Dairy Farm

The spread of antibiotic-resistant bacteria in the environment is raising serious public health concerns, and manure is being increasingly recognized as a major source of antibiotic-resistant bacteria. In this research, we isolated Escherichia coli and enterococci from manure produced in a Wisconsin, USA family dairy farm to determine their resistance to six representative antibiotics. The average densities for E. coli and enterococci were 6.37(±4.38)?×?10⁷ colony formation units (CFU)?g^?1 and 1.60(±1.57)?×?10⁴ CFU g^?1, respectively. The E. coli isolates were found to be resistant to cephalothin, ampicillin, tetracycline, and erythromycin. In addition to these four antibiotics, the Enterococcus isolates were also resistant to gentamicin and ciprofloxacin. Additionally, we examined the survival and growth of E. coli and enterococci in dairy manure over a period of ~3 days. While the densities of enterococci remained stable over the study period, the concentrations of E. coli on average increased by 1.5 log10 units. Further tests of the bacterial antibiotic resistance over time showed no significant changes in the prevalence of antibiotic resistance. This result indicated that slightly aged manure could represent a larger source of antibiotic-resistant E. coli than fresh manure and the accumulation of antibiotic-resistant E. coli and enterococci in the agricultural fields must be accounted for in the modeling of the spread of antibiotic-resistant bacteria in the environment.     

Small-Scale Composting of Horse Manure Mixed with Wood Shavings

There is an increased interest in composting manure on small horse farms (1-5 horses). It is known that simple backyard, food waste composters do not efficiently reduce pathogens due to their small scale. However, it was not clear if small-scale manure composting on horse farms could ensure pathogen reduction during all seasons. Furthermore, because of potential human health concerns, the release of Aspergillus fumigatus on small horse farms was of interest. The objective of this study was to evaluate pathogen reduction in a simple shed composter and the release of Aspergillus fumigatus emissions from fall to spring under typical farm operational conditions. Horse manure mixed with wood shavings (bedding) was composted for 4-8 weeks in the fall, winter, early spring and late spring. Fecal streptococci and eggs of strongyles, which are a major recognized health concern for horses, were used as pathogen indicator organisms. Temperatures increased in all composting piles during all seasons, but tended to be higher in warmer weather. After 4 weeks, the fecal streptococci reduction was about 10- to 100-fold and, after 8 weeks, about 100- to 1000-fold. There was some effect of season on fecal streptococci levels, with the higher composting temperatures appearing to provide greater reductions. Strongyle eggs in this study were very low and were reduced over time. Levels of viable A. fumigatus spores during turning ranged from 12-2084 CFU m^?3, while background levels ranged between 6 - 300 CFU m^?3. Overall, this study indicates that composting horse manure mixed with wood shavings reduces pathogens. A. fumigatus levels are elevated during turning, but the levels are lower than those found at sewage sludge/municipal solid waste composting facilities or inside barns.     

Soil Physical Properties and Organic Matter Fractions Under Forages Receiving Composts,Manure or Fertilizer

A field study was conducted to assess the benefits, with respect to soil physical properties and soil organic matter fractions of utilizing composts from a diversity of sources in perennial forage production. A mixed forage (timothy-red clover (Trifolium pratense L.) and monocrop timothy (Phleum pratense L.) sward were fertilized annually with ammonium nitrate (AN) at up to 150kg and 300 N ha^?1 yr^?1, respectively, from 1998-2001. Organic amendments, applied at up to 600 kg N ha^?1 yr^?1 in the first two years only, included composts derived from crop residue (CSC), dairy manure (DMC) or sewage sludge (SSLC), plus liquid dairy manure (DM), and supplied C to soil at 4.6 and 9.2 (CSC), 10.9 (SSLC), 10.0 (DMC) 2.9 (DM) Mg C ha^?1. Soil samples (0-5cm; 5-10cm;10-15cm) were recovered in 2000 and 2001. Improvements in soil physical properties (soil bulk density and water content) were obtained for compost treatments alone. Composts alone influenced soil C:N ratio and substantially increased soil organic carbon (SOC) concentration and mass (+ 5.2 to + 9.7 Mg C ha^?1). Gains in SOC with AN of 2.7 Mg C ha^?1 were detectable by the third crop production year (2001). The lower C inputs, and more labile C, supplied by manure (DM) was reflected in reduced SOC gains (+ 2.5 Mg C ha^?1) compared to composts. The distribution of C in densiometric (light fraction, LF; >1.7 g cm^?3) and particulate organic matter (POM; litter (>2000μm); coarse-sand (250-2000μm); fine-sand (53-250μm) fractions varied with compost and combining fractionation by size and density improved interpretation of compost dynamics in soil. Combined POM accounted for 82.6% of SOC gains with composts. Estimated compost turnover rates (k) ranged from 0.06 (CSC) to 0.09 yr^?1 (DMC). Composts alone increased soil microbial biomass carbon (SMB-C) concentration (μg C g^?1 soil). Soil available C (C_ext) decreased significantly as compost maturity increased. For some composts (CSC), timothy yields matched those obtained with AN, and SOC gains were derived from both applied-C and increased crop residue-C returns to soil. A trend towards improved C returns across all treatments was apparent for the mixed crop. Matching composts of varying quality with the appropriate (legume/nonlegume) target crop will be critical to promoting soil C gains from compost use.     

Treatment of Source-Separated Human Feces via Lactic Acid Fermentation Combined with Thermophilic Composting

Human feces from urine diverting dry toilets can serve as valuable soil conditioners. For a successful agricultural application, an efficient pathogen reduction needs to be ensured, with no negative effects on plants. This study assessed the efficiency of lacto-fermentation combined with thermophilic composting on pathogen removal from human feces and the post-treatment effects on germination and growth of radish (Raphanus sativus) and tomatoes (Lycopersicum esculentum) compared to lacto-fermentation combined with vermi-composting and the control. The NH₄⁺-N/NO₃^?-N ratio of 3.0 and 3.6, respectively, suggested the obtained compost and vermi-compost was not yet mature. A complete reduction in the concentration of all investigated bacterial indicators (i.e., coliforms, Escherichia coli, Enterococcus faecalis, and Clostridium perfringens) from 5–7 log CFU g^?1 to below detection limit (<3 log CFU g^?1) was achieved after lacto-fermentation combined with thermophilic composting. Lacto-fermentation combined with vermi-composting also contributed to pathogen die-off, but coliform bacteria were reduced to only 5 log CFU g^?1. Fertilization of seeds of radish by compost obtained after lacto-fermentation combined with thermophilic composting led to a higher germination index than by the vermicast obtained by lacto-fermentation and vermi-composting (90% versus 84%). Moreover, significantly bigger average fruit weight and total biomass per tomato plant (p < 0.05) were obtained after compost amendment compared to vermicast or the control.     

Fungal flora of soil polluted with copper

The effects of copper pollution on the soil fungal flora was investigated. Soils treated with 100, 200, 400, 800 or 1600 μg Cu g^?1 were used for experiments to study changes in fungal populations, especially the development and dominance of copper-tolerant fungi. Fungi were sampled 1, 3 and 5 months after copper treatment.All the correlation coefficients between the copper contents and the number of fungal colonies plated were positive. The higher the copper concentration in soil, the more 1000 μ Cu ml^?1 tolerant fungi were isolated. The relative number of 1000 μg Cu mr^?1 tolerant fungi from the soil treated with 1600 μg Cu g^?1 was about 30% of those of the control 14 days after treatment. Within the limits of this experiment, the increase in fungal populations was directly correlated with the increase of dominant Cu-tolerant fungi.From control soils, containing low quantities of copper, 1000 μg Cu ml^?1 tolerant fungi were also isolated; whereas, from soils containing high amounts of copper, some Cu-sensitive fungi were isolated. Most of the 1000 μg Cu ml^?1 tolerant fungi were Penicillium spp. It was concluded that the genus Penicillium may be dominant in soils polluted with copper.     

Partitioning the Nutrient and Nonnutrient Contributions Of Compost to Dryland-Organic Wheat

Organic materials supply nutrients to plants but may also have other, nonnutrient-related benefits which are more difficult to quantify. This study partitioned the winter wheat (Triticum aestivum L.) yield response from compost applications into nutrient and nonnutrient fractions. Composted dairy manure and wheat straw bedding was applied at five rates (0, 10, 25, 50, and 75 Mg dry weight ha^?1) to dry-land wheat in an organic wheat-fallow farming system. The compost was fall-applied and incorporated prior to planting at adjacent sites in sequential years. Maximum grain yield increases from compost application ranged from 2,139 kg ha^?1 in a year with 186% of average annual precipitation to 1,324 kg ha^?1 in a year with 87% of average annual precipitation. The Mitscherlich equation was used to describe the yield response to compost rate. The nutrient and nonnutrient contributions of compost to grain yield were partitioned by solving the Mitscherlich equation for compost rates where applied nutrients were in surplus (≥25 Mg ha^?1), calculating a non-nutrient Mitscherlich response function, and subtracting the nonnutrient response function from the full response to determine the nutrient contribution across compost rates. At the 10 Mg ha^?1 compost rate, the nonnutrient to nutrient yield response ratio varied from 0.25:1 for the year with above average precipitation to 2.2:1 for the year with below average precipitation. Compost significantly increases dry-land wheat yields. These results suggest that nonnutrient benefits of compost applications may be significant and exceed nutrient benefits under dryland production in low rainfall years.     

Effect of Municipal Solid Waste Compost and Farmyard Manure Application on Heavy‐Metal Uptake in Wheat

The risks related to municipal solid waste compost application in comparison to farmyard manure and mineral fertilizers on durum wheat were investigated on a short‐term experiment. Compost was applied at 40 t ha^?1 and 80 t ha^?1 with or without chemical fertilizers. Analogously, farmyard manure was applied at 40 t ha^?1. Both compost and farmyard manure improved plant growth and nutrient uptake. However, compost amendment showed more effectiveness, especially at 80 t ha^?1. Alternatively, this dose of compost involved an increase of plant copper, cadmium, and zinc concentrations in plant tissues. Metal accumulation did not thwart the enhancement of wheat yield. Furthermore, grain translocation factor reached 1 only in the case of copper; however, it showed a significant decrease following compost application (ranged between 0.57 and 0.69). Bioconcentration factor showed a significant decrease with municipal solid waste compost supply, constituting an internal detoxification mechanism.