Vermicomposting Of Pig Manure Research Articles

Effect of Exogenous Organic Matter on Phosphorus Forms in Middle-High Fertility Cinnamon Soil.

To slow down the chemical fixation of phosphate fertilizer, reduce the risk of active phosphorus leaching, stimulate the inherent phosphorus resource activity of soil, and improve phosphorus supply capacity. This study utilized a combination of field experiments and indoor chemical analysis. Six types of exogenous organic matter (fulvic acid, biochar, compound microbial fertilizer, high-energy microbial inoculum, pig manure-vermicompost, cow manure-vermicompost) were added based on conventional fertilization. The experiment was conducted under the wheat-maize rotation system in the Huang-Huai-Hai region. Compared with control (CK) without exogenous organic matter (EOM), all the other treatments with EOM had an enhancing effect on the available phosphorus of the cultivated soil. During the maize harvest, the combined application of biochar, pig manure-vermicompost and cow manure-vermicompost treatment significantly increased the content of available phosphorus in 0-20 cm soil by 45.87-56.59% compared with CK. The combined application of fulvic acid, biochar, pig manure-vermicompost and cow manure-vermicompost treatment significantly increased the content of Ca2-P in 0-20 cm soil by 34.04-65.14%. The content of Ca10-P in each treatment with EOM exhibited a lower level compared to CK. EOM could slow down the fixation of phosphorus to some degree. Correlation analysis revealed significant associations between Ca2-P, Ca8-P, Al-P, Fe-P, neutral phosphatase activity, acid phosphatase activity, and the available phosphorus content in the soil. The combined application of fulvic acid, biochar, and cow manure-vermicompost could enhance the activity of neutral and acid phosphatase in topsoil to a certain extent, thereby facilitating the conversion of phosphorus into highly available Ca2-P. EOM could enhance the soil phosphorus availability and decelerate the conversion of soil phosphorus into O-P and Ca10-P forms with low availability. Among all treatments, biochar exhibited the most pronounced efficiency in mitigating phosphorus leaching downward. All the EOMs had the potential to enhance the conversion of phosphorus into soluble phosphorus (Ca2-P), thereby mitigating the chemical fixation of soil phosphorus and ameliorating non-point source pollution caused by phosphorus. EOM enhanced the activity of neutral and acid phosphatase, which was beneficial to the conversion of organic phosphorus to inorganic phosphorus and increasing the content of available phosphorus. All EOMs had good effects on the retention of soil effective phosphorus, among which biochar had the best effect on retaining effective phosphorus in the tillage layer and blocking phosphorus leaching downward.

Impacts of vermicompost application on crop yield, ammonia volatilization and greenhouse gases emission on upland in Southwest China

Ammonia (NH3) volatilization and greenhouse gas (GHG) emission are important environment pollution sources in upland agro-ecosystems. Vermicompost was used for amending purple soil and comparing NH3 and GHG emissions. A field experiment was conducted with a comparison of organic and inorganic fertilizers in a wheat–maize rotation system in the Sichuan Basin, China. The five treatments were conventional inorganic fertilizers, NPK as control; vermicompost prepared with cow dung (VCM); and pig manure (VPM); cow dung and pig manure vermicompost, respectively (VCMNPK, VPMNPK). Total nitrogen rates of all treatments were the same. Soil NH3 volatilization and GHG emissions were monitored with the static chamber method. The results showed that NH3 volatilization occurred in the first two weeks following nitrogen (N) fertilization. The cumulative fluxes of NH3 recorded in the NPK, VCM, VPM, VCMNPK, and VPMNPK treatments were 15.4, 5.7, 6.3, 10.32, and 10.29 kg N ha−1 yr−1, respectively, in the winter and 4.8, 5.5, 19.83, 12.8, and 11.9 kg N ha−1 yr−1 respectively, in the summer. The global warming potential (GWP) 773.6 and 803.9 g CO2-eq m−2 in VCM and VPM, respectively, during the wheat season 540.6 and 576.2 g CO2-eq m−2, respectively, during the maize season. The GWPs in NPK treatment were 1032.4 and 570.7 g CO2-eq m−2 during the wheat and maize seasons, respectively. The increasing effects of nutrient loops, particularly 18 % soil total nitrogen (TN) and 31 % soil organic carbon (SOC) in VCM, and crop productivity of vermicompost treatments during the wheat–maize rotation had been evaluated. This study recommends that VCM can be considered as a better organic amendment, promoting plant growth while decreasing the environmental costs of gas emissions.

Vermicompost Amended With Rock Phosphate as a Climate Smart Technology for Production of Organic Swiss Chard (Beta vulgaris subsp. vulgaris)

Vermicomposting is being promoted as climate-smart agriculture (CSA) technology for developing organic nutrient sources that can be adopted by smallholder farmers. The amendment of soils with cost-effective and available inorganic fertilizers like rock phosphate (RP) and phosphorus-solubilizing microorganisms should also be promoted. Our study investigated the seedling and maturity growth of Swiss chard. The crop maturity study investigated the effect of amending an Oxisol soil with three phosphorus (P) sources applied at three different rates (0, 25, and 50 mg P kg−1 soil), cow and pig manures, and P-solubilizing bacteria resulting in the following treatments: control (soil), soil + RP alone, soil + RP-enriched cow manure vermicompost (VC) with phosphorus-solubilizing bacteria (PSB), and soil + RP-enriched pig manure vermicompost (VP) with PSB. The study investigated the growth performance and accumulation of copper (Cu), zinc (Zn), chromium (Cr), and lead (Pb) in the edible parts of Swiss chard (Beta vulgaris subsp. valgaris var. Cicla). The seedlings were grown using pine bark compost and the three P sources (VC, VP, and RP) at five different application rates (0, 25, 50, 75, and 100%). The results revealed that the use of 50 mg P kg−1 as VP gave the highest fresh weight of 39.78 g, leaf area of 240.41 cm2, and a total P in tissues of 326.91 mg kg−1 at 8 weeks after transplanting. The 50 mg P kg−1 application as VC resulted in a higher Zn content of 8.50 mg kg−1, which was above the permissible level. These results suggest that the best treatment mixture for establishing fully matured Swiss chard was the 50 mg P kg−1 as VP. Therefore, pig manure vermicompost that has been inoculated with phosphorus-solubilizing microorganisms is a promising CSA technology that can improve organic vegetable production by smallholder farmers.

Differential Effects of Organic Amendments on Maize Biomass and Nutrient Availability in Upland Calcareous Soil

The current study is focuses on a sustainable agricultural ecosystem for soil fertility and human health improvement. To estimate the effects of applying organic amendments (compost, vermicompost, biochar, organic manure and rapeseed cake) on crop growth of maize and nutrient uptake in calcareous soil, eleven treatments were studied, which included compost (CM), cow manure vermicompost (CMV), pig manure vermicompost (PMV), biochar vermicompost (BCV), biochar (BC), conventional synthetic fertilizers (NPK), CMV in addition to NPK (CMV + NPK), and PMV in addition to NPK (PMV + NPK), organic manure (OM), rapeseed cake (RC) and control without any fertilization (CK). Maize above and belowground biomass were analyzed in glass greenhouse experiments. The results showed that nitrogen and carbon contents showed significant differences among treatments. Vermicompost significantly showed higher biomass as compared to inorganic fertilizers except for RC. All vermicompost treatments also showed better nutrient availability as compared to NPK and CK. In conclusion, vermicompost with all substrates are recommended for application as organic fertilizers. Our study will help promote the application of organic fertilizers alone or in combination with inorganic fertilizers rather than only inorganic fertilizers for environmental health and sustainability.

Humic acid characterization and heavy metal behaviour during vermicomposting of pig manure amended with 13C-labelled rice straw.

Aiming to reveal the humification process of organic waste and its contribution to the heavy metal behaviour affected by earthworm activity, it was studied about the variation of humic acid (HA) and heavy metal behaviour during vermicomposting of the mixed pig manure and 13C-labelled rice straw. The results showed that earthworms could well adapt to the culturing environment and feed organic matter for its growth and reproduction, the vermicomposting process increased the content of humic substances (HS), HA, and fulvic acid (FA) in substrate residues, but led to less transformation of HA into FA. The elemental, ultraviolet absorption spectroscopy, Fourier transform infrared (FTIR) and fluorescence excitation-emission matrix (EEM) analysis indicated that vermicomposting led to more aromatic structures and much higher humification degree in HA, whereas less protein, FA-like substances and plastein in HA. Vermicomposting could enhance the total Cu content and decrease Cu/Zn bioavailability in the substrate residues, and vermicomposting especially can help stabilize Cu in the substrate residues by forming more complexed HA-Cu.

Effects of Gleditsia sinensis pod powder, coconut shell biochar and rice husk biochar as additives on bacterial communities and compost quality during vermicomposting of pig manure and wheat straw

This study investigated the effectiveness of Gleditsia sinensis pod powder (GSPP), coconut shell biochar (CSB), rice husk biochar (RHB) and their mixtures on vermicomposting of pig manure and wheat straw using Eisenia fetida. The results indicated that the addition of GSPP or/and CSB and RHB could greatly enhance the relative abundance of Bacteroidetes, Actinobacteria, and Firmicutes, as well as the activities of celluloses, protease, and alkaline phosphatase. However, the earthworm biomass was increased in the GSPP and/or CSB addition treatments but decreased in RHB addition treatments compared with the control. Compared with the control, addition of 4%GSPP+8%CSB significantly (P < 0.05) accelerated the degradation of organic matter and increased the concentration of nutrients (total N, P, K), NO3--N in final vermicompost. Germination and growth of tomato seedings were also higher (P < 0.05) in vermicompost produced with the addition of 4%GSPP+8%CSB than in control. Consequently, 4%GSPP+8%CSB addition was suggested as an efficient method to improve the vermicomposting of pig manure and wheat straw.

Evaluation of temperature on the biological activities and fertility potential during vermicomposting of pig manure employing Eisenia fetida

In this laboratory-scale study, the biological activities and vermicomposting potential of Eisenia fetida in pig manure were investigated to evaluate the influence of temperature (10°C–50 °C) on vermicomposting effect. The enzyme activities of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and the content of malondialdehyde (MDA) in earthworm, macro-nutrients (N, P, K), total organic carbon (TOC), humification index (HIX) and C/N ratio in pig manure have been investigated simultaneously. Results revealed that CAT activity elevated initially and then declined with the increased temperature. The increased POD, SOD activity and MDA content indicated the antioxidant stress response of earthworm and the optimum temperature was found at 30 °C. After vermicomposting the pig manure for 60 d under temperature range of 10°C–50 °C, the vermicompost exhibited a significant increase in macro-nutrients, whereas a reduction was observed in TOC, C/N ratio and HIX, reflecting the efficient decomposition of organic waste driven by earthworms and microorganisms synergistically. The result of total microbial population showed the increase of actinomycetes and bacterial population. The enhancement percentage was in the order: 30 °C > 40 °C > 50 °C > 20 °C > 10 °C, revealing the impact of temperature. The results indicated the advantage of vermicomposting with Eisenia fetida and the regulation mechanism of temperature on the vermicomposting effect of pig manure. The present study will benefit to the utilization of agricultural wastes and achieving environmental sustainability.

Nutrients Recovery during Vermicomposting of Cow Dung, Pig Manure, and Biochar for Agricultural Sustainability with Gases Emissions

An experimental vermicomposting system was established in purple soil present in Sichuan Basin, China. The purpose of vermicomposting (VC) was to recycle and manage organic waste materials; for instance, animal manure and crop residues are present in great quantity. A particular use of earthworms for VC is a valuable method for retrieving essential plant nutrients. Experimental vermicomposting followed by monitoring was conducted for two months in summer with an interval of fifteen days. Four treatments, COM (compost without earthworms), VCM (using cow manure), VPM (through pig manure), and VBC (using biochar), were applied with agricultural wastes such as rapeseed and wheat straw in combination with cow dung, pig manure, and biochar, respectively. One-way analysis of variance (ANOVA) was used to statistically analyze and interpret the nutrient change among different treatments. Post hoc analysis was done using Tukey’s test. The experimental vermicomposting results revealed that VCM gives increased plant nutrients with a minimum C: N ratio (from 22.13 to 14.38) and a maximum increase in nitrogen concentrations (1.77 to 29.15 g kg−1). A significant decrease in ammonia volatilization was observed in the order VCM &gt; VBC &gt; VPM when compared to COM. It was experimentally established that vermicomposting is the most suitable method for converting organic waste into nutrient-rich fertilizer with the least environmental pollution load.

Influence of Microbial Inoculation of Igneous Rock Phosphate-Amended Cow and Pig Manures on Vermidegradation and Nutrient Release

Vermicomposting using Eisenia fetida has been shown to improve phosphorus mineralization from rock phosphate (RP). There is, however, a lack of information on the potential of integrating microbial inoculants like phosphate-solubilizing bacteria (PSB) during vermicomposting as a way of improving vermidegradation, and the release of nutrients from igneous RP-amended composts. This study evaluated the potential of using Eisenia fetida and Pseudomonas fluorescence in enhancing the vermidegradation, and nutrient release in igneous RP- amended cow and pig manure-based vermicomposts at a C/N ratio of 30. Compost maturity, nutrient and phytotoxicity parameters were measured to determine vermicompost quality. Final vermicompost results showed that the pig manure treatments achieved greater maturity as indicated by lower C/N of 10.3, high humification index (HI) of 7.6%, and humification ratio (HR) of 12.89% in the treatment with E. fetida and P. fluorescence. The inclusion of E. fetida alone in cow manure treatment resulted in the highest Olsen P of 2600 mg/kg, followed by the pig manure treatment with E. fetida only (2246.15 mg/kg). In conclusion, both E. fetida and P. fluorescence are necessary in the vermicomposting of RP-enriched pig and cow manure for efficient vermi-degradation and nutrient release.

Heavy metal and δ13C value variations and characterization of dissolved organic matter (DOM) during vermicomposting of pig manure amended with 13C-labeled rice straw.

In this work, a mixture of pig manure and 13C-labeled rice straw was vermicomposted with Eisenia fetida for 40days. The results showed that after they acclimated to the vermicomposting environment, the earthworms helped to degrade the substrate residues. After 40days, the vermicomposting led to much higher pH, EC, C/N, available K, available P, available Zn, and CEC values but much lower available N and available Cu values in the substrate residues compared to the initial values. The earthworms accumulated 13C, Cu, and Zn with a heavy metal enrichment capacity in the order of Cu > Zn. Furthermore, the correlation analysis showed that the Cu and Zn content in the DOM was mainly controlled by the Cu and Zn content in the pig manure. The earthworms accumulated Cu and Zn by feeding on the substrate residues, but the DOM from the 13C-labeled rice straw helped to extract Zn from the substrate residues and promoted the migration of Zn into the earthworm tissues and/or DOM. Moreover, the characterization of the DOM extracted from the substrate residues revealed a decrease in the content of the aliphatic alcohols or polysaccharide-like substances and an increase in the aromatic compounds and fulvic or humic acid-like substances in the DOM as the vermicomposting time increased. This indicated that the higher humification degree in the DOM caused by vermicomposting contributed to the increased mobility of Zn in the substrate residues and helped Zn migrate into the earthworms or DOM.

Product quality and microbial dynamics during vermicomposting and maturation of compost from pig manure

This research evaluates, through microbial dynamics, the use of earthworms Eisenia andrei for maturation of pre-composted pig manure in comparison with maturation under static conditions and with vermicomposting of fresh pig manure. Therefore, two substrates were used (fresh and pre-composted pig manure) and four treatments were developed: fresh manure vermicomposting, control of fresh manure without earthworms, pre-composting followed by vermicomposting and static maturation of pre-composted manure. In order to determine the microbial dynamics, the enzymatic activities and profiles of phospholipid fatty acids (PLFAs) were evaluated over a 112-days period. Physicochemical and biological parameters of the obtained products were also analyzed. The presence of earthworms significantly reduced (p<0.05) microbial biomass and all the microbial groups (Gram+bacteria, Gram−bacteria, and fungi) in both substrates. The enzymatic activities (cellulase, β-glucosidase and acid phosphatase) behaved in a significantly distinctive manner (p<0.05) depending on the treatment. Microbial communities had significant correlations (p<0.05) with hydrolytic activities during static maturation of pre-composted manure. This indicates a direct effect of microbiota evolution on the degradative processes; however, complex earthworm-microbiota interactions were established in the presence of E. andrei. After earthworms’ removal from vermicompost of fresh substrate at 70day, an increase in Gram + (4.4 times), Gram − (3.8 times) and fungi (2.8 times) were observed and, although the vermicompost achieved quality values, it is necessary to optimize the vermicompost aging phase period to improve the stability. Static maturation presented stability on microbial dynamics that indicated a slow degradation of organic compounds so that, maturation of pre-composted manure through vermicomposting is better option.

INTERPRETING RESULTS FOR PLANT GROWTH PROMOTION AND DISEASE SUPPRESSION BIOASSAYS USING COMPOST

Applying high rates of humified, thermophilic compost and vermicompost to a soil depleted in organic carbon has the potential to improve soil structure and soil fertility, and also to suppress soilborne disease. In this paper, published bioassay methods were used to assess the disease-suppressing properties of cured, thermophilic cotton trash Applying high rates of thermophilic compost and vermicompost to a soil depleted in organic carbon has the potential to improve soil structure and fertility, and to suppress soilborne disease. Published bioassay methods were used to assess the disease-suppressing properties of three cured cotton trash composts, and the plant growth promoting properties of filtrate produced from pig manure vermicompost. The chemical properties of the composts and the Fusarium wilt infested receiving soil were analysed, to assess other soil health parameters likely to affect plant growth. Results were not as expected. Cotton seedling survival in the compost treatments was only marginally better than the control, with all seedlings showing disease symptoms. In the plant growth promotion assay, seed germination was highest in the water-only controls, with the vermi- and mesophilic (no worm) compost filtrates inhibiting root growth. The common factor responsible for the unexpected results was excessive salinity. To realize the soil health benefits of organic amendments, application rates must account for the concentration of plantavailable nutrients and soluble salts that they contain.

Pig manure vermicompost (PMVC) can improve phytoremediation of Cd and PAHs co-contaminated soil by Sedum alfredii

Purpose A major challenge to phytoremediation of co-contaminated soils is developing strategies for efficient and simultaneous removal of multiple pollutants. A pot experiment was conducted to investigate the potential for enhanced phytoextraction of cadmium (Cd) by Sedum alfredii and dissipation of polycyclic aromatic hydrocarbons (PAHs) in co-contaminated soil by application of pig manure vermicompost (PMVC).

Replacing Conventional Nursery Crop Nutrient Inputs with Vermicompost for Container Production of Hibiscus moscheutos L. ‘Luna Blush’

Vermicomposting of pig manure is a waste management approach that has been shown to be economically and technologically feasible and yields a value-added end product, vermicompost (VC), that contains plant-available nutrients. The objective of this study was to determine if conventional nursery crop inputs could be replaced by commercially available VC (derived from pig manure) for production of Hibiscus moscheutos ‘Luna Blush’ L. (hibiscus). Hibiscus was grown in 3.8-L containers containing pine bark amended with 11% sand (by vol.), 1.8 kg·m−3 dolomitic limestone, and 0.9 kg·m−3 micronutrient package (PBS) or pine bark amended with 20% VC (by vol.) (20VC). Plants were topdressed with one of three controlled-release fertilizers (CRF) containing only nitrogen (N); N and potassium (K); or N, phosphorus (P), and K. The four treatments included PBS with 17–6–12 (PBS + NPK), 20VC with 17–6–12 (20VC + NPK), 20VC with 17–0–12 (20VC + NK), and 20VC with 17–0–0 (20VC + N). The PBS + NPK treatment, which was supplied with conventional nursery crop nutrient inputs (limestone, sulfated micronutrients, and CRF containing NPK), served as the control treatment to represent the industry standard. All treatments were irrigated to maintain a leaching fraction (LF = volume leached ÷ volume applied) of 0.24. Daily inorganic nitrogen (IN-N) and dissolved reactive phosphorus (DRP) effluent contents were determined. Plants were harvested at 35 and 56 d after potting (DAP). Total plant nutrient contents of P, calcium (Ca), magnesium (Mg), and sulfur (S), iron (Fe), manganese, zinc (Zn), copper (Cu), and boron (B) were equivalent or greater for all three 20VC treatments compared with PBS + NPK. However, total plant K content of 20VC + N was less than 20VC + NPK, 20VC + NK, and PBS + NPK. Regardless of lower K content in the 20VC + N treatment, all three 20VC treatments had equivalent total plant dry weight and number of flowers. Furthermore, all three 20VC treatments averaged 58% and 40% greater plant dry weight than PBS + NPK at 35 and 56 DAP, respectively, and 93% more flowers than PBS + NPK at 56 DAP. All three 20VC treatments had similar IN-N and DRP effluent contents. However, the three 20VC treatments averaged 4.3× more IN-N effluent content and 59× DRP effluent content than PBS + NPK. The nutrient use efficiencies for all treatments were similar, in which nitrogen use efficiency ranged from 9% to 15% and phosphorus use efficiency ranged from 7% to 12%. In conclusion, this source of VC provided equivalent or greater P, Ca, Mg, S, Fe, Zn, and Cu but less K for plant uptake compared with the industry standard (control) treatment and produced larger plants with more flowers than the control. This suggests that dolomitic lime, sulfated micronutrients, and P can be eliminated as substrate additives.

Microbial and nutrient stabilization of two animal manures after the transit through the gut of the earthworm Eisenia fetida (Savigny, 1826)

Here we studied how the transit through the gut of the earthworm Eisenia fetida affects the microbial and nutrient stabilization of pig and cow manure, by analyzing fresh casts. Earthworms reduced the pools of dissolved organic C and N in casts from both types of manure, as wells as mineral N. Microbial biomass was enhanced only in casts from pig manure and did not change in casts from cow manure, and fungal populations only raised in casts from cow manure. Earthworms reduced microbial activity in casts from cow manure and did not modify in casts from pig slurry. Enzyme activities in casts also depended on the manure ingested; there were no changes in dehydrogenase and β-glucosidase activities, whereas acid and alkaline phosphatases increased. The results indicate that the first stage in vermicomposting of pig and cow manure by E. fetida, i.e. casting, produced a microbial stabilization decreasing the activity of microorganisms; this stabilization occurred despite of the increase in microbial biomass. The strong reduction in nutrient pools of manures may be the responsible of this contradiction. These changes will influence the dynamics of the organic matter degradation by reducing forms of C and N available to microorganisms and hence restricting their growth and multiplication. Nevertheless, casts were also characterized by an increased enzyme potential that might lead to a further thorough degradation of pig and cow manure.

The influence of humic acids derived from earthworm-processed organic wastes on plant growth

Some effects of humic acids, formed during the breakdown of organic wastes by earthworms (vermicomposting), on plant growth were evaluated. In the first experiment, humic acids were extracted from pig manure vermicompost using the classic alkali/acid fractionation procedure and mixed with a soilless container medium (Metro-Mix 360), to provide a range of 0, 50, 100, 150, 200, 250, 500, 1000, 2000, and 4000 mg of humate per kg of dry weight of container medium, and tomato seedlings were grown in the mixtures. In the second experiment, humates extracted from pig manure and food wastes vermicomposts were mixed with vermiculite to provide a range of 0, 50, 125, 250, 500, 1000, and 4000 mg of humate per kg of dry weight of the container medium, and cucumber seedlings were grown in the mixtures. Both tomato and cucumber seedlings were watered daily with a solution containing all nutrients required to ensure that any differences in growth responses were not nutrient-mediated. The incorporation of both types of vermicompost-derived humic acids, into either type of soilless plant growth media, increased the growth of tomato and cucumber plants significantly, in terms of plant heights, leaf areas, shoot and root dry weights. Plant growth increased with increasing concentrations of humic acids incorporated into the medium up to a certain proportion, but this differed according to the plant species, the source of the vermicompost, and the nature of the container medium. Plant growth tended to be increased by treatments of the plants with 50–500 mg/kg humic acids, but often decreased significantly when the concentrations of humic acids derived in the container medium exceeded 500–1000 mg/kg. These growth responses were most probably due to hormone-like activity of humic acids from the vermicomposts or could have been due to plant growth hormones adsorbed onto the humates.

How earthworm density affects microbial biomas and activity in pig manure

We studied the influence of the earthworm, Eisenia fetida, on the microbial populations during the vermicomposting of pig manure. Fresh pig manure was placed in replicated boxes with (two densities, 25 and 50) and without earthworms for a period of 16 d. Samples were destructively collected periodically and analyzed for microbial biomass nitrogen, microbial respiration, substrate-induced respiration (SIR) and substrate dehydrogenase activity. Microbial biomass N, microbial respiration, SIR and substrate dehydrogenase activity were significantly lower in the earthworm treatments after 8 d.

The influence of earthworm-processed pig manure on the growth and productivity of marigolds

The effects of additions of earthworm-processed pig manure (vermicompost) on the growth and productivity of French marigold ( Tagetes patula) plants were evaluated under glasshouse conditions. Marigolds were germinated and grown in a standard commercial greenhouse container medium (Metro-Mix 360), substituted with 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% (by volume) pig manure vermicompost. The control consisted of Metro-Mix 360 alone without vermicompost. Plants were supplied regularly with a complete mineral nutrient solution for 121 days. The greatest vegetative growth resulted from substitution of Metro-Mix 360 with 30% and 40% pig manure vermicompost, and the lowest growth was in the potting mixtures containing 90% and 100% vermicompost. Most flower buds occurred in the potting mixtures containing 40% pig manure vermicompost (19.4 buds), and fewest in the potting mixtures containing 100% vermicompost. Marigolds grown in Metro-Mix 360 substituted with 90% and 100% pig manure vermicompost had the fewest and smallest flowers. After substitution of Metro-Mix 360 with 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90% vermicompost, the marigold roots were larger than those of plants grown in the Metro-Mix 360 controls. Substitution of Metro-Mix 360 with any concentration of pig manure vermicompost, with all needed nutrients provided, increased the overall nitrate–nitrogen concentrations of the marigold leaf tissues at flowering stage. Some of the marigold growth and productivity enhancement, resulting from substitution of Metro-Mix 360 with pig manure vermicompost, may be explained by nutritional factors; However, other, factors, such as plant-growth regulators and humates, might have also been involved since all plants were supplied regularly with all required nutrients.

Pig manure vermicompost as a component of a horticultural bedding plant medium: effects on physicochemical properties and plant growth

This experiment was designed to characterize the physical, chemical and microbial properties of a standard commercial horticultural, greenhouse container, bedding plant medium (Metro-Mix 360), that had been substituted with a range of increasing concentrations (0%, 5%, 10%, 25%, 50% and 100% by volume) of pig manure vermicompost and to relate these properties to plant growth responses. The growth trials used tomatoes ( Lycopersicon esculentum Mill.), grown in the substituted media for 31 days under glasshouse conditions, with seedling growth recorded in 20 pots for each treatment. Half of the tomato seedlings (10 pots per treatment) were watered daily with liquid inorganic fertilizer while the other half received water only. The percentage total porosity, percentage air space, pH and ammonium concentrations of the container medium all decreased significantly, after substitution of Metro-Mix 360 with equivalent amounts of pig manure vermicompost; whereas bulk density, container capacity, electrical conductivity, overall microbial activity and nitrate concentrations, all increased with increasing substitutions of vermicompost. The growth of tomato seedlings in the potting mixtures containing 100% pig manure vermicompost was reduced, possibly as a result of high soluble salt concentrations in the vermicompost and poorer porosity and aeration. The growth of tomato seedlings was greatest after substitution of Metro-Mix 360 with between 25% and 50% pig manure vermicompost, with more growth occurring in combinations of pig manure vermicompost treated regularly with a liquid fertilizer solution than in those with no fertilizer applied. Some of the growth enhancement in these mixtures seemed to be related to the combined effects of improved porosity, aeration and water retention in the medium and the high nitrate content of the substrate, which produced an increased uptake of nitrogen by the plant tissues, resulting in increased plant growth. When the tomato seedlings were watered daily with liquid inorganic fertilizer, substitution of Metro-Mix 360 with a very small amount (5%) of pig manure vermicompost resulted in a significant increase in the growth of tomato seedlings. Such effects could not be attributed solely to the nutritional or physical properties of the pig manure vermicompost. Therefore, it seems likely that the pig manure vermicompost provided other biological inputs, such as plant growth regulators into the container medium, that still need to be identified fully.

Influence of earthworm-processed pig manure on the growth and yield of greenhouse tomatoes

The effects of earthworm-processed pig manure (vermicompost) on germination, growth, and yields of tomato ( Lycopersicon esculentum Mill.) plants were evaluated under glasshouse conditions. Tomatoes were germinated and grown in a standard commercial greenhouse container medium (Metro-Mix 360), substituted with 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% (by volume) pig manure vermicompost. The control consisted of Metro-Mix 360 alone without vermicompost. Plants were grown for 158 days and were frequently supplied with a complete mineral nutrient solution. The germination rates of tomato seeds increased significantly upon substitution of Metro-Mix 360 with 20%, 30%, and 40% vermicompost. Seedlings grown in 100% pig manure vermicompost were significantly shorter, had fewer leaves, and weighed less than those in Metro-Mix 360 controls. Incorporation of 10% or 50% vermicompost into Metro-Mix 360 increased the dry weights of tomato seedlings significantly compared to those grown in the Metro-Mix 360 controls. The largest marketable yield was in the substitution of Metro-Mix 360 with 20% vermicompost (5.1 kg/plant). The average weight of a tomato fruit in substitution of Metro-Mix 360 with 20% vermicompost was 12.4% greater than that in the Metro-Mix 360 control. Substitution of Metro-Mix 360 with 10%, 20%, and 40% vermicompost reduced the proportions of fruits that were non-marketable, and produced more large size (diameter > 6.4 cm) than small size (diameter < 5.8 cm) tomato fruits. There was no significant difference in overall tomato yields between Metro-Mix 360 and 100% pig manure vermicompost. Some of the growth and yield enhancement resulting from substitution of Metro-Mix 360 with pig manure vermicompost could be attributed to the high mineral N concentration of the pig manure vermicompost. However, other factors might have also been involved since all plants were frequently supplied with all required nutrients. These factors need to be investigated in future studies.