Volume 4 Special Issue 1 2010
How to reference: Munnoli PM, Teixeira da Silva JA, Bhosle S (2010) Dynamics of the Soil-Earthworm-Plant Relationship. In: Karmegam N (Ed) Vermitechnology II. Dynamic Soil, Dynamic Plant 4 (Special Issue 1), 1-21
Vinayaka Missions University, India
CONTENTS AND ABSTRACTS
Prakash Mallappa Munnoli (India), Jaime A. Teixeira da Silva (Japan), Saroj Bhosle (India) Dynamics of the Soil-Earthworm-Plant Relationship: A Review (pp 1-21)
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Invited Review: Increases in the human population, indiscriminate growth of cities, industrialization, and agricultural practices have led to an increased accumulation of waste materials. The present method of disposal by open dumping has made the problem more acute by disturbing the soil-air-water ecosystem, thus needing urgent attention by planners. Moreover, the most abundantly available biomass, the lignocelluloses, have attracted considerable attention as an energy resource because of their large quantity. The recovery of nutrients by modification of wastes like municipal solid waste, industrial solid waste, agricultural residues, and animal wastes, etc. is important for their management and for reducing environmental degradation. Also, the deleterious impact on the environment by chemical fertilizer urges the need for production of organic manure out of waste. Recycling organic wastes through vermiculture biotechnology is being considered as an economically viable solution. Earthworms are considered as natural bioreactors which proliferate along with other microorganisms and provide required conditions for the biodegradation of wastes. The present study examines the various dynamics of the soil-earthworm-plant relationship with special emphasis on vermiculture. The assesses the following topics: earthworm biodiversity, earthworm species for waste management, substrates, consumption rates, enzyme activities, medicinal uses of earthworms, methods of vermicomposting along with their advantages and disadvantages, impact of application of vermicompost to soil fertility, soil microorganisms and crop yield, characteristics of vermicomposts, sustainable agriculture, economic importance and future prospects.
Rajiv K. Sinha, Sunil Herat (Australia), Natchimuthu Karmegam (India), Krunal Chauhan, Vinod Chandran (Australia) Vermitechnology - The Emerging 21st Century Bioengineering Technology for Sustainable Development and Protection of Human Health and Environment: A Review (pp 22-47)
Invited Review: Vermitechnology is emerging as an environmentally sustainable, economically viable and socially acceptable technology all over the world consisting of several categories: vermi-composting (management of most organic wastes); vermi-filtration (treatment of municipal and several industrial wastewaters); vermi-remediation (treatment and clean up of contaminated lands); vermi-agroproduction (production of chemical-free foods by worms and vermicompost); vermi-protection (protection of human health by medicines from worms); vermi-production (production of valuable industrial raw materials from worms). The use of earthworms in composting of waste and in farm production were known for ages but have now been scientifically and commercially revived. The other uses of earthworms for the benefits of environment and society (wastewater treatment, land remediation and production of valuable medicines even to combat cancer and heart diseases are some new discoveries). We have successfully experimented with the first four technologies for management of municipal solid wastes, treatment of municipal and industrial wastewater, remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils and production of wheat and corn crops by use of vermicompost at Griffith University, Australia, with excellent results. Wastes are degraded >75% faster than conventional systems and compost produced are disinfected, detoxified, richer in nutrients and beneficial soil microbes; BOD loads and TSS of wastewater is reduced by over 95%; PAHs from contaminated soils are removed by over 80% in just 12 weeks; and growth of crops is promoted by 30-40% more than with chemical fertilizers. Earthworms are both protective and productive for environment and society.
K. A. Gopinath, Bandi Venkateswarlu, Banshi L. Mina, K. C. Nataraja, Konda Gayatri Devi (India) Utilization of Vermicompost as a Soil Amendment in Organic Crop Production (pp 48-57)
Invited Review: The use of vermicompost (VC) has long been recognized as an effective means of increasing crop yields through improved soil physical, chemical and biological properties. Since synthetic mineral fertilizers are disallowed in organic crop production, there has been a renewed interest in recycling wastes into valuable organic fertilizer through vermicomposting and its subsequent utilization in organic crop production. This review summarizes published data on influence of VC on productivity and quality of crops and on soil properties particularly under organic management. Several researchers have reported that VC application give marginally lower or comparable crop growth and yield under organic management compared with that of mineral fertilizers. Furthermore, it has been well established that VC application significantly improves overall health of soil. Hence, VC has the potential to become a major soil amendment in organic crop production.
Birinchi K. Sarma, Pratibha Singh, Susheel K. Pandey, Harikesh B. Singh (India) Vermicompost as Modulator of Plant Growth and Disease Suppression (pp 58-66)
Invited Review: Vermicompost (VC) is a rich source of macro- and micro-nutrients and is used to enliven soils. It is mostly considered as an efficient supplement of organic matter to soils and horticultural container media low in organic content. Recently VC has also been explored extensively for its various other useful activities especially its role in enhancing plant growth promoting effect as well as in suppression of plant diseases by various mechanisms. VC is considered superior to conventional compost especially for substitution of soils or greenhouse container media for its ability to modify soil properties in a better way. The role of VC in plant growth promotion is largely believed to be due to its nutrient rich composition as well as its ability to modify soil physical and chemical properties suitably in a way to favor plant growth and development. Among its role in suppression of plant pathogens and nematodes, it is believed that it modulates a plant’s innate resistance response to resist microbial attack. Apart from this, VC-mediated soil physicochemical properties also favors growth and multiplication of saprophytic soil microbes including the biocontrol agents and thus helps in enhancing performance of most biocontrol agents against a wide range of phytopathogens. VC prepared from various sources and methods have also been identified to playing different roles in promoting plant growth and achieving biological management of phytopathogens. In the present review various roles and mechanisms of VC as plant growth regulator and disease suppressor unearthed recently are discussed.
Takeshi Hirano, Kazuyoshi Tamae (Japan) Earthworms, as a Bio-monitor of Metal Contamination in Soil (pp 67-71)
Invited Mini-Review: Although heavy metal pollution of soil causes biological problems, such as genotoxicity to living organisms, including human beings, few methods have been developed to assess metal mutagenicity in soil. To avoid metal mutagenicity, an adequate bio-monitoring method is required. Earthworms can be used as a bio-monitor of metal contamination in soil, because significant positive correlations have been found between the concentrations of metals, such as cadmium, copper, lead, and zinc, in the earthworm and the concentrations of these metals in the soil. Although many studies have been performed to establish bio-monitoring methods using earthworms, there have been few reports of bio-monitoring for soil mutagenicity. Recently, we examined the possibility of using earthworms in a bio-monitoring method for mutagenicity due to soil pollutants, such as metals. In the study, we analyzed the generation of 8-oxoguanine (8-oxo-Gua) in earthworms exposed to cadmium and nickel in soil. 8-Oxo-Gua is a major premutagenic form of oxidative DNA damage that induces GC-to-TA point mutations in genome DNA, leading to carcinogenesis. In this review, the use of earthworms as a bio-monitoring method for metal pollution in soil is described.
Alimardon Rakhmatullaev, Laziza Gafurova, Dilfuza Egamberdieva (Uzbekistan) Ecology and Role of Earthworms in Productivity of Arid Soils of Uzbekistan (pp 72-75)
Invited Mini-Review: Earthworms are key components of terrestrial ecosystems, however, little is known about their ecology, distribution, and taxonomy in arid saline soils of Uzbekistan. This report summarizes the main issues about the ecology of earthworms and their impact on soil properties and plant productivity in saline arid soils. A total of 21 earthworm species belonging to seven different families, viz., Allolobophora, Aporrectodea, Eisenia, Eisenilla, Dendrobaena, Dendrodrilus and Octolasion were identified, of which the species Allolobophora taschkentensis, A. ferganae, A. kaznakovi and Aporrectodea roseus are endemic for Uzbekistan. The species of Aporrectodea trapezoides and Aporrectodea caliginosa dominate the earthworm fauna in arid saline soils of Uzbekistan. The diversity and number of earthworms are decreasing under cotton cultivation and increase under lucerne. Furthermore, the application of animal manure and crop rotation increased earthworm density and biomass.
Grazia Masciandaro, Veronica Bianchi, Cristina Macci, Eleonora Peruzzi, Serena Doni, Brunello Ceccanti, Renato Iannelli (Italy) Ecological and Agronomical Perspectives of Vermicompost Utilization in Mediterranean Agro-ecosystems (pp 76-82)
Original Research Paper: Fields experiments were conducted to treat an agronomic soil using three types of fertilizers: organic (vermicompost), mineral, and a mixture of organic and mineral (vermicompost + NPK), added to soil with two N application doses (100 and 200 kg/ha). Vermicompost was obtained through aerobic stabilization of biological sludge, performed by earthworms (Eisenia fetida). The soil was cropped with maize (Zea mays) and sunflower (Helianthus annuus). Plant productivity and effects of treatments on soil chemical and biochemical properties were evaluated. Results showed an increase of plant productivity (expressed as kg of seeds produced per plot) in the treatment with vermicompost and mineral fertilizer, for both plant species and application rates. Mineral fertilization reduced soil microbial activity and increased the release of carbon and nitrogen soluble compounds suggesting a degradation of native soil organic matter and impacting on environmental quality.
Sudhir D. Ghatnekar, Mahavash F. Kavian, Santosh M. Sharma (India), Sumukh S. Ghatnekar (UK), Gautam S. Ghatnekar, Angela V. Ghatnekar (USA) Application of Vermi-filter-based Effluent Treatment Plant (Pilot scale) for Biomanagement of Liquid Effluents from the Gelatine Industry (pp 83-88)
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Original Research Paper: The present paper describes the application of three-tier vermiculture biotechnology coupled with vermi-filtration to convert secondary liquid effluents from a gelatine manufacturing unit into ‘bio-safe’ clean water. The experiments were conducted at a pilot scale. The protocol involved pretreatment of selected effluents using a combination of protease and cellulase. Later, mixed cultures of Aspergillus flavus (BRC - 27), A. niger (BRC - 28), Nitrobacter winogradskyi (BRC - 5), Spirulina platensis (BRC - 45), Oscillatoria princeps (BRC - 46) and Chlorella vulgaris (BRC - 47) were inoculated. The effluents were then passed through a series of 3 vermi-filter (VF) tanks, the uppermost layer of each consisting of bedding material inoculated with selected enzymes, microorganisms and colonies of Lumbricus rubellus that served as biofilters followed by a trickling filter system. The final vermi-filtered water exhibited a significant decrease in COD by 90.08 ± 0.176%, and BOD by 89.24 ± 0.544%. In 3 months, the total CFU in the upper bedding layer of specific VF tanks exhibited an exponential increase indicating expected degradation potential of the organic matter in the effluents. The bedding material gradually converted into humified vermicompost on which seedlings of Canna indica were planted. The final vermi-filtered discharge was clean and its bio-safety was evaluated by using it for secondary purposes, irrigation and Spirulina cultivation.
Meena Khwairakpam, Renu Bhargava (India) Vermicomposting of Cattle Manure using Mono- and Polycultures of Three Earthworm Species (pp 89-95)
Original Research Paper: Vermicomposting can be the most economical and sustainable option for cattle waste management. Therefore, three different earthworm species Eisenia fetida, Eudrilus eugeniae, Perionyx excavatus in individual (monoculture) and combinations (polyculture) were utilized to conserve the potential nutrients from cattle manure. Vermicomposting resulted in lowering of pH, total organic carbon (TOC), C/N ratio, coliforms and increase in electrical conductivity (EC). Macronutrients (Na, K and Ca), total nitrogen (TN) and total phosphorous (TP) was observed to increase with vermicomposting time, clearly indicating the conservation of potential nutrients from cattle manure. Compost stability studies revealed that the final compost became very stable with a final oxygen uptake rate (OUR) of 2.68-3.11 mg g-1 volatile solids (VS) day-1 and 2.12-2.87 mg g-1 VS day-1. Therefore, it is evident that vermicomposting can be carried out in mono as well as polycultures without any mortality.
Santhebennur Jayappa Veeresh, Jogattappa Narayana (India), Jaime A. Teixeira da Silva (Japan) Influence of Jeevamrutha (Biodynamic Formulation) on Agro-Industrial Waste Vermicomposting (pp 96-99)
Original Research Paper: This study aimed to determine the influence of cow dung and a biodynamic microbial consortium (jeevamrutha) on the microbial population during the conversion of papermill and sugar factory sludge into beneficial vermicompost. The bacterial and actinomycete densities were highest in the jeevamrutha-treated group and fungal density was higher in the treatment group treated with cow dung. The microbial density in earthworms of treatment groups inoculated with or without microbial culture was significantly different to that of the control group. Furthermore, there was a significant relationship between microbial density and treatment groups. The inoculation of microbial consortia like jeevamrutha and cow dung together with organic substrates significantly enhances the microbial density throughout the process of decomposition.
G. Selladurai, N. Anbusaravanan (India), Jaime A. Teixeira da Silva (Japan), K. Prakash Shyam, Balamuthu Kadalmani (India) Dynamics of Microbial Diversity, Micro- and Macronutrients during Tannery Sludge Treatment Using Epigeic Earthworms, Eisenia fetida and Eudrilus eugeniae (pp 100-107)
Original Research Paper: Indiscriminate and uncontrolled discharge of metal-contaminated industrial effluents into the environment has become an issue of major concern in developing countries. The vermicomposting of organic material with earthworms minimizes environmental pollution and health hazards. Organic and inorganic minerals in earthworm casts are high and have positive effects; pollution can be solved using vermicomposting. Tannery effluent is one of the common industrial effluents containing poisonous heavy metals and toxic compounds such as zinc, copper, iron, manganese, chromium and others. This manuscript describes the improved nutrient availability and decreased toxic effect of tannery effluent, through vermicomposting, after treatment with two earthworms, Eudrilus eugeniae and Eisenia fetida. The latter were as beneficial as the former in terms of vermicomposting potential. A favorable environment for microbial diversity was achieved at an optimum sludge ratio of 1: 2: 2 and 2: 2: 1 when mixed with normal soil in its lethal concentration (55.5 and 54% (v/w), respectively for E. eugeniae and E. fetida). Thus, we recommend E. eugeniae and E. fetida in the agricultural use of soils contaminated with tannery sludge and tannery effluent.
Kunwar D. Yadav, Vinod Tare, M. Mansoor Ahammed (India) Influence of Soil Characteristics on Biomass Growth and Reproduction of Earthworm Eisenia fetida (pp 108-112)
Original Research Paper: It is known that in vermicomposting soil layer in bedding of the reactor helps in earthworm biomass growth and reproduction but growth is influenced by soil characteristics such as texture, pH, and water holding capacity. The present study was conducted to asses the influence of soils on earthworm biomass growth and reproduction during the vermicomposting of source separated human faeces. The study was conducted by using the earthworm species Eisenia fetida with agriculture, saline and sandy soils. The study utilized reactors with SVFV combination (soil, vermicompost, faeces and vermicompost - bottom to top layers). All sets of reactors were examined monthly for four months for growth of earthworms and offspring production. The results of the study indicated that biomass growth of earthworms and offspring production were in the order: sandy soil > agricultural soil > saline soil. The multiplication of earthworm was 3.8-5.5–fold within 4 months. Vermicomposting helped to improve the soil characteristics such as carbon and nitrogen content, pH and conductivity.
Swati Pattnaik, M. Vikram Reddy (India) Effects of Urban Organic Wastes, their Composts and Vermicomposts on the Growth Traits of Fenugreek (Trigonella foenum-graecum L.) and Tomato (Lycopersicum esculentum Mill.) under Field Conditions (pp 113-122)
Original Research Paper: Three types of urban wastes – municipal solid waste (MSW), vegetable market waste (MW) and floral waste (FW) were bio-converted to composts (Cs), and vermicomposts (VCs) using three earthworm species – Eudrilus eugeniae (Kinberg), Eisenia fetida (Savigny)and Perionyx excavatus (Perrier). These were applied at a rate of 5 and 10 t ha-1 under field conditions, and their effects on various growth traits of fenugreek (Trigonella foenum-graecum L. South Indian cultivar) (‘UM-9’) and tomato plant(Solanum lycopersicum) (cv. ‘Arka’) were assessed. These experiments were conducted with a randomized complete block design. The urban organic wastes and their Cs and VCs showed significant positive effects on the growth of different traits of both plants (P < 0.001). There was a significant positive correlation between the number of leaves and dry biomass of both plants. The shoot length, number of leaves, number of branches, and dry biomass of both the plants increased significantly, except the root length, which decreased with the application of urban wastes and their Cs and VCs compared to the same traits of plants grown in soil. Growth traits, except for root length, were significantly higher with the application of VCs than those when Cs and urban organic wastes were used and were ranked as: VCof E. eugeniae > VC of E. fetida > VCof P. excavatus > C > wastes – MW > MSW > FW. This is because the VCs produced by these earthworm species possessed higher contents of nutrients – nitrogen, phosphorus, potassium, calcium and magnesium – compared to the C and urban organic wastes.
Shilpa Shrimal, Meena Khwairakpam (India) Effect of C/ N ratio on Vermicomposting of Vegetable Waste (pp 123-126)
Original Research Paper: A study (42 days duration) was conducted to evaluate the best C/N (carbon: nitrogen) ratio for vermicomposting of vegetable waste blended with cow dung and saw dust by analysis of various parameters i.e. pH, total organic carbon (TOC), electrical conductivity (EC), total nitrogen (TN), chemical oxygen demand (COD) and metals, for this study an exotic earthworm species- E. fetida was used. Four different reactors R1, R2, R3 and R4 with C/N ratios of 20, 30, 40 and 16.4, respectively were tested. After 42 days of vermicomposting, it was found that C/N ratio significantly affected the growth and reproduction of E. fetida. The decrease in COD varied significantly (p<0.05) in all the three reactors R1, R2 and R3 with highest percentage decrease in R2 which was found to be 78.02% while in R1 and R3 it was 66.64% and 75.78% respectively. The increase in TN content varied significantly in all the reactors on all the days (p<0.05) with maximum percentage increase of 73.58% in R2 as compared to 42.51% and 61.62% in R1 and R3, respectively.
Stephanie Birch, Richard Bell, Jaya Nair (Australia), Cao Van Phung (Vietnam) Feasibility of Vermicomposting Aquaculture Solid Waste on the Mekong Delta, Vietnam: A Pilot Study (pp 127-134)
Original Research Paper: The disposal of aquaculture waste from freshwater pond systems on the Mekong Delta, Vietnam, is causing serious pollution of waterways. Currently, there are few treatment options available for aquaculture wastes. This study investigates the use of vermicomposting to treat the solid component of the waste, aquaculture sludge (AS). Perionyx excavatus was used to vermicompost various proportions of AS, rice straw (RS) and water hyacinth (WH). Worm mortality rates ranged from 28 to 77% but there were no significant differences between treatments. Worm reproduction appeared to be increased where higher proportions (> 80%) of AS were used however the treatment with 100% AS had the lowest number of juvenile worms (1.3 ± 0.3 per 50 g substrate). Total N increased significantly with increasing bulking material and final values ranged from 0.4 to 0.9%. Total phosphorus (P), potassium (K), manganese (Mn), magnesium (Mg), calcium (Ca), and available P and K were significantly higher in treatments with WH than treatments with RS as a bulking material due to the initial composition of this material. It was concluded that AS from freshwater pond systems on the Mekong Delta can be effectively treated by vermicomposting and may have potential for subsequent use as an agricultural fertiliser.
Senguttuvan Sarojini, Govindarajan Manimegala, Mani Prakash, Sriramulu Ananthakrishnasamy, Govindarajan Gunasekaran (India) Vermicomposting of Lignite Flyash Reduces its Genotoxicity and Phytotoxicity and Improves its Agronomic Values for Application as Soil Amendments in Farmlands: A Study of Vermicomposted Flyash on Onion Crops (Allium cepa) (pp 135-138)
Original Research Paper: The aim of this study was to evaluate the toxic potential of flyash by Allium cepa and also to understand the effect of vermicomposting on the reduction of toxicity, if any. Morphological studies of A. cepa roots indicated coiled and wavy roots following exposure to flyash, but no root abnormality was reported in vermicompost (VC). Under genotoxic studies, mitotic index (MI) was inhibited. The MI in cow dung (CD) was 9.52 which was reduced to 7.30 in FA, whereas MI increased to 11.43 in the CD + FA mixture and 15.76 in vermicomposted FA. The wet weight of roots and chlorophyll (Chl) contents were reduced in FA, but not so in VC. The wet weight of A. cepa roots in CD was 28.1 g on the 60th day which was reduced to 23.9 g in FA, while VC showed an increase to 36.4 g on the 60th day. The content of both Chl a and b decreased in FA and increased more in VC than in CD. Simultaneously Chl a and b content increased more in the CD + FA mixture than in FA but decreased in VC. It can be concluded that FA was toxic but vermicomposting of FA might be beneficial for bioremediation and thus could be used in agriculture.
Asha Aalok, Ashutosh Kumar Tripathi (India) Composting-Vermicomposting of Different Types of Leaves using Earthworm Species Eisenia fetida (pp 139-144)
Original Research Paper: The aim of this work was to study the variation in the nutrient quality of compost and vermicompost produced from leaf litters of different plant species namely, Eucalyptus hybrid, Pinus roxburghii, Populus deltoides,and Shorea robusta and leaves of Parthenium hysterophorus, mixed with municipal solid waste and to assess the potential of Eisenia fetida in composting different types of leaf litter. Cow dung was used as control in composting and vermicomposting experiments. In the first part of the experiment, vermicomposting resulted in a significant reduction (P < 0.001), in pH (0.26-7.2% in compost and 2.29-19.99% in vermicompost), C/N ratio (40.53-60.41% in compost and 47.55-69.21% in vermicompost) and an increase in the percent total nitrogen (12.66-76.17% in compost and 47.0-145.5% in vermicompost), total phosphorous (10.14-87.14% in compost and 26.45-121.84% in vermicompost), total potassium (9.90-68.40% in compost and 20.96-106.18% in vermicompost), total calcium (2.34-13.93% in compost and 11.07-24.66% in vermicompost), and total magnesium (6.63-27.02% in compost and 14.47-66.05% in vermicompost). The second part of the experiments revealed that that E. fetida preferred the feed in following order: cowdung (control) > PoLMSWV > ParLMSWV > EuLMSWV > PiLMSWV > SrLMSWV. The earthworms consistently gained in weight and produced offspring in all the reactors, throughout the experiment. The results show that the nutrient quality of the final product depends on the initial properties of the material used. The hypothesis that quality of the substrate material influences the worms feeding as well as growth efficiencies has also been confirmed by this study.
Prakash Mallappa Munnoli (India), Jaime A. Teixeira da Silva (Japan), Saroj Bhosle (India) Geotechnical Properties of Vermicomposts of Press Mud using Eisenia fetida, Eudrilus eugeniae and Megascolex megascolex (pp 145-151)
Original Research Paper: Studies were carried out to evaluate the geotechnical properties of vemicomposts (VCs) such as porosity, void ratio, density, air content, water holding capacity and particle size distribution (PSD) prepared from sugar industrial waste press mud (PM) using surface feeders Eisenia fetida, Eudrilus eugeniae andthedeep burrower Megascolex megascolex. A comparison of the geotechnical properties of 40-day samples of VCs from field trials by a core cutter showed that the VC using M. megascolex was superior to E. eugeniae and E. fetida VCs in terms of water and air content and percentage void. The PSD of PM was higher than industrial soil, while M. megascolex VC > E. fetida VC > E. eugeniae VC (P < 0.05).This depicts an inverse bioconversion or grinding capacity of the three earthworms: E. eugeniae > E. fetida > M. megascolex. This study clearly indicates that the indigenous deep burrower M. megascolex can be used in the vermicomposting of PM while also enhancing the geotechnical properties, soil aggregation and water holding capacity of a VC.
Thilagavathy Daniel, Balayogan Sivasankari, Muthu Malathy (India) Microbial and Nutrient Enhancement of Gliricidia sepium and Leucaena leucocephala Leaf Materials Using Eisenia fetida (pp 152-154)
Short Communication: Pre-decomposed (15 days) leaves of Gliricidia sepium and Leucaena leucocephala were mixed with cowdung (1: 1: 2) and subjected to vermicomposting (60 days) using an exotic earthworm, Eisenia fetida Savigny. The same substrate was kept without earthworms as control. Worm-worked (vermicompost) and worm-unworked substrates were separately analyzed for electrical conductivity (EC), pH, organic carbon, NPK and colony-forming units (CFU) of bacteria, fungi and actinomycetes. Activity of E. fetida increased the EC, NPK and microbial CFU. The initial bacterial population of 188±1 × 106 CFU g-1 increased gradually during vermicomposting and it was 281.67±1.15 × 106 CFU g-1 on the 45th day. A similar trend was also observed for fungi and actinomycetes. The results reveal that the leaf leaves of G. sepium and L. leucocephala can be converted into microbial- and nutrient-rich vermicompost using E. fetida.
Norliyana Sailila, Azizi Abu Bakar, Noor Zalina Mahmood (Malaysia), Jaime A. Teixeira da Silva (Japan), Noorlidah Abdullah, Adi Ainurzaman Jamaludin (Malaysia) Nutrient Elements of Different Agricultural Wastes from Vermicomposting Activity (pp 155-158)
Short Communication: Vermicomposting using the earthworm Lumbricus rubellus was conducted for 70 days subsequent to 10 days of pre-composting under glasshouse conditions. Five treatments were used as feed materials with 5 replicates per treatment: T1: goat manure, T2: paddy straw, T3: spent mushroom paddy straw compost, T4: sawdust and T5: spent mushroom sawdust compost. The treatments were placed in a microcosm or worm bin plastic container (360 mm × 280 mm × 200 mm). The effectiveness of vermicomposting was evaluated through the increment of nutrient elements contained in the vermicompost, growth (biomass weight) and reproduction (total numbers) of earthworms, as a percentage, at the end of the process. The increment of macronutrients in the vermicompost from each treatment was high, especially of organic carbon (C) in T1 and T4, and nitrogen (N), phosphorous (P) and potassium (K) in T3. Regarding micronutrients, copper (Cu) had the highest concentration in T2 and zinc (Zn) in T1 and T2. Therefore, the best vermicompost as a soil fertilizer was T3, which showed the highest increment and final content of N (+150.73%, 1.50%), P (+387.75%, 1.06%) and K (+886.09%, 2.05%). There was no significant difference between the number and weight of earthworms among the 5 treatments (P > 0.05). A C: N ratio < 20 indicates the degree of compost maturity and post-vermicomposting, as noted for T1 and T3; T1 had the lowest C: N ratio (9.86). Based on our findings, the nutritive value of our vermicompost – developed from selected agricultural wastes – can be qualitatively assessed as a value-added material against fertilizers or soil stabilizers.
Timothy J. Smith, William T. Stringfellow (USA) Identification of Factors from Agricultural Runoff Water on the Viability of Embryos of the Earthworm Dendrobaena veneta (pp 159-161)
Research Note: Agricultural runoff water (inlet and outlet points of water storage ponds) was evaluated for its effect on earthworm using Dendrobaena veneta. Chemical analysis revealed a significant difference in pH, phosphate and inorganic nitrogen from inlet and outlet samples as well as differences in embryo viability. Among the factors tested, pH was the most important factor for viability, while phosphate and nitrate appeared to stimulate the development of the embryos. These results demonstrate the utility of Dendrobaena veneta, a water-tolerant earthworm species useful for environmental water testing.