Bio-digestion and post-treatment of effluents by bio-fermentation, an opportunity for energy uses and generation of organic fertilizers from bovine manure Abstract Purpose Bio-fermentation has been routed as a viable alternative for the treatment of organic waste, which can provide renewable energy and can return nutrients to the soil with its byproducts. In this context, the objectives of the research were to analyze the benefits that a plastic plug-flow bio-digester can provide for treatment of bovine manure; and through bio-fermentation to control the E. coli number present in the bio-digester effluents. Methods The concentration of macronutrients and amount of the E. coli in the effluent was determined by the methods of analysis purposed by APHA standard methods and AOAC standard methods, respectively. In addition, the percentage composition of biogas was analyzed for determining the operative of the system. Results The production of biogas showed of 52.55% mol of methane concentration which it fed one blowtorch and one kitchenette. The bio-digester effluents showed appreciable amounts of nitrogen, potassium, phosphates, calcium, magnesium and sodium but with E. coli presence; the reason why the bio-digester effluent was treated later by a second fermentation inoculated with mountain effective microorganism, post-treatment which eliminated in 100% E. coli presence. Conclusion Both processes showed the viability as treatment of the bovine manure which brings renewable energy and effluents with nutritive loads to use it as a biofertilizer without risks to health and humanity. The project was located at the tropical zone into the Choco forest, at an average altitude of 1110 m above sea level and an average temperature annual of 21–22 °C.

Growth and metabolic activities of cowpea seedlings exposed to artificial pond wastewater-treated soil Abstract Purpose The increase in demand for fish has necessitated the establishment of fish pond. The discharge of spent pond water pollutes the adjoining surroundings. The aim of this investigation was to determine the suitability of artificial pond wastewater (APWW) as source of manure for crop cultivation. Method Cowpea seeds were planted in polybags containing soil treated with varied amount of artificial pond wastewater. Thereafter, growth and various metabolic properties of cowpea seedlings were determined using standard procedures. Results Artificial pond wastewater treatment of soil increased significantly (P < 0.05) the growth parameters, content of biomolecules and activities of alpha amylase, starch phosphorylase and peroxidase when compared to the control. Exposure of the seedlings to APWW did not alter most oxidative stress markers compared to the control. In addition, APWW in soil significantly (P < 0.05) increases the levels of vitamin C but had no alterations in the activities of succinate dehydrogenase (SDH), lactate dehydrogenase (LDH) and sulphite oxidase (SO) of the cowpea seedlings compared to those of the controls. The activities of aldehyde oxidase (AO) and xanthine oxidase (XO) significantly (P < 0.05) increased compared with the control. Conclusion The major effects of APWW on plants were stimulation of growth parameters, increase in concentration of macromolecules as well as increase in activities of starch-metabolizing enzymes, and peroxidase activity with no adverse effect on antioxidant, respiratory and drug-metabolizing enzymes, thus, suggesting that artificial pond wastewater has positive effect on cowpea seedlings and can act as organic fertilizer for cowpea cultivation.

Cultivation of straw mushroom ( Volvariella volvacea ) on oil palm empty fruit bunch growth medium Abstract Purpose The research aimed to study the effects of size reduction and composting duration of empty fruit bunches (EFB) on straw mushroom production, and to examine the doses of fertilizers commonly used among farmers. Methods The experiment was done in two stages. The first stage was for identifying the optimum physical parameters of EFB, and the second stage focused on enhancing the performance of EFB chosen based on the findings of the first experiment. A randomized complete block design with 3 × 3 factorial arrangement in both stages of the study used the same approach. The first stage had three levels of aggregate sizes factor (S) and three levels of composting duration factor (C) of EFB. The second stage had three levels of NPK factor (N) and three levels of organic fertilizer factor (O). Results Whole stalk EFB had the highest productivity of 2458.47 ± 1015.23 g m−2. The supplementation of fertilizers increased the EFB decomposition rate and productivity to 2950.24 ± 208.50 g m−2, and nutritive values (particularly for protein content of 41.00 ± 3.79%). Averaged biological conversion efficiency (BCE) was also improved from 3.61 ± 1.22 to 6.56 ± 0.46%. Conclusions EFB did not need to be cut into smaller pieces, and should not be composted for more than 8 days, because there was a tendency to decrease yield. Supplemental fertilizers increased the decomposition rates of EFB as well as the yield and nutritive values of straw mushroom. BCE can potentially be improved by increasing the dosages of fertilizers.

Fabrication of a vermifiltration unit for wastewater recycling and performance of vermifiltered water (vermiaqua) on onion ( Allium cepa) Abstract Purpose Vemifiltration units are sludge-free, noise-free and low- or no-electricity-requiring systems of operation. The aim of this study was to emphasize wastewater treatment by vermifiltration technology using waste-eater earthworms to highlight the benefits of clean and nutritive vermifiltered water (vermiaqua) uses in agriculture to the farmers. Methods Wastewater sample was filtered through fabricated vermifiltration unit to study physio-chemical and biological properties of vermiaqua and uniform-sized Allium cepa (Onion) bulbs were kept for root germination at different concentrations (10−1, 10−3, 10−5, 10−7, 10−9) of wastewater and vermiaqua at room temperature for 5 days to study impacts of vermiaqua on morphological and cytological characteristics of onion. Results Vermiaqua was odorless, pale yellow in appearance, lower in turbidity and highly nutritive as ammonia and nitrate contents were highly increased. In E. coli-free vermiaqua, BOD5 loads were also reduced by 91%. Almost all vermiaqua-treated root germinations were ‘accelerated’, whereas all wastewater-treated root germinations were ‘retarded’. The highest number of germinated roots was counted at 10−5 concentration of vermiaqua, whereas at the same concentration of wastewater no germination was observed. Many types of chromosomal abnormalities were observed at metaphase and anaphase stages of wastewater-treated roots, whereas the single type of chromosomal abnormality was observed at anaphase stage of vermiaqua-treated roots. Conclusions Earthworms upgraded the performance of fabricated systems having integrated methods (biological, chemical and physical) of wastewater purification. Morphological and cytological studies revealed vermiaqua highly promoted the root germination without any chromosomal abnormalities.

Effect of the composting process on physicochemical properties and concentration of heavy metals in market waste with additive materials in the Ga West Municipality, Ghana Abstract Purpose The main objective of this study was to assess the physiochemical properties and phytotoxicity of compost made from different organic waste materials sourced from local markets. Methods The Stack pile composting was carried out with market waste, sawdust, rice straw, and swine manure in four different combinations. Parameters such as temperature, pH, nitrogen, phosphorus, potassium, and heavy metal concentrations were monitored. Germination test with water extracts of the composts was done to assess phytotoxicity of the composts. Results All compost piles recorded temperatures of 38 °C slightly above the recorded ambient temperature of 34 °C at the start of composting. The pH value ranged from 7.12 to 8.2 for the different compost types. The total organic carbon and total nitrogen values ranged from 27.05–31.06 to 0.77–0.97%, respectively. The total phosphorus and total potassium values ranged from 0.2–1.87 to 0.39–2.3%, respectively, for different compost types. The C/N ratio values ranged from 29.09:1 to 36.22:1. All the composts had heavy metal concentrations below the Canadian Council of Ministers of the Environment standards. Germination indices, a measure of plant vs supporting potential, ranged from 80 to 99% for Solanum lycopersicum, 170 to 198% for Cucumis sativus, and 114 to 166% for Brassica oleracea. Conclusion The study confirms the notion that composting municipal solid waste is a viable organic waste management strategy, and with the potential to enhance waste management system, while promoting cultivation of vegetables for food security.

Liquid organic fertilizer production for growing vegetables under hydroponic condition Abstract Purpose Liquid organic fertilizers produced from agricultural residues and industrial wastes are becoming increasingly popular. This study aimed to examine the effect of liquid organic fertilizers produced from waste molasses, distillery slop and sugarcane leaves on the growth of Green Cos Lettuce (Lactuca sativa var. longifolia). Methods Six formulas of liquid organic fertilizers were produced with different ratios of substrates (molasses, distillery slop and sugarcane leaves). The measurements of chemical, microbiological and germination index of fertilizers were studied. Hydroponic using nutrient film technique system was used to grow vegetables with fertilizers. Results Fertilizers showed the ranges of chemical parameters as follows: pH 4.5–7.8, EC 25–33 dS/m, total N 0.14–0.33%, total P2O5 0.002–0.017%, total K2O 0.81–11.8%, OM 0.26–3.25%, OC 0.26–3.20% and C:N ratio 6.14–17.92. Microbiological analysis indicated total microorganism of 9.99–9.05 logCFU/ml. Nitrogen fixers, phosphate and potassium solubilizing agents were found in all formulas. IAA concentration was 1.13–59.53 mg/l. The fertilizers produced after 30 days of fermentation and used at a dilution of 1:100 gave more than 100% germination index showing non-phytotoxicity characteristics. The results for the hydroponic system showed that liquid fertilizer formula 3 (distillery slop: sugarcane leaves: filtrate water 1:0.1:0.25 v:w:v) and formula 5 (distillery slop: sugarcane leaves 1:0.25:0.25 v:w:v) demonstrated the best growth performance, which was similar to plants treated with liquid chemical fertilizer. Conclusion This study showed that organic liquid fertilizers formulas 3 and 5 had similar growth promotion properties as chemical fertilizers with Green Cos Lettuce. Moreover, our products are organic and serve as a rich nutrient source for the plant.

Food waste in animal feed with a focus on use for broilers Abstract Purpose Although the world’s food production is approximately 3.99 billion metric tons, one in nine people remain malnourished. In combination with the projected world population of nine billion by 2050, further malnourishment of both humans and animals may occur; therefore, understanding of the current status of food waste and reuse is important. Methods An extensive literature review was conducted to quantify food waste by weight and percentage at harvesting, processing/manufacturing, wholesale, retail, and consumer sectors of the food supply chain. The analysis of food waste was considered globally, within the United States, and within the state of California (USA). Results Large amounts of food waste (meat, vegetables, fruits, and breads) are produced daily. Results of the previous research suggest that food waste can be used successfully in diets of monogastric animals. Conclusions The poultry industry is growing globally and uses large amounts of corn and soy for poultry diets; therefore, research should be conducted to investigate the partial use of alternative feed ingredients to meet the growing demand for poultry production. We proposed that food waste, occurring in all sectors of the food supply chain, could become a partial substitute for corn and soy in broiler diets.

Impact of agricultural waste on the shrink–swell behavior and cracking dynamics of expansive soils Abstract Purpose The swelling characteristics and cracking of expansive clayey soils usually lead to their low yield, and as a result, large areas of expansive soils remain uncultivated and unproductive. There is a need for the development of simple, low-cost technologies which will bring these soils into production. The amendment of expansive clayey soils with agricultural waste products is a key goal for enhancing their production potential. Therefore, a study was conducted to evaluate the ameliorative effects of crop residues on the physiochemical and mechanical properties of expansive clayey soils. Method In this study, the potential soil amendments used include uncharred rice husk, rice husk biochar, uncharred sugarcane bagasse, and sugarcane bagasse biochar. The biochar was pyrolyzed at 450 °C. The amendments were applied into the soil at four applications rates: 0, 2, 5, and 10% by weight of soil (w/w), respectively. The mixture was then incubated in a glasshouse for 280 days. Results Charred and uncharred rice husk and sugarcane bagasse improved the physico-mechanical properties related to soil expansion. The liquid limit (LL), plastic limit (PL), plasticity (PI), coefficient of linier extensibility (COLEcore), volumetric shrinkage (VS), fissures’ dimensions, and crack area density (CAD) of the soil decreased with an increase in treatment application rate. On the contrary, saturated water content increased with an increase in dosage. Conclusions 10% level of amendment application resulted in significantly improved soil properties than either 2% or 5% doses. Moreover, 2% level of amendment application is more preferable than 5% according to feasibility and economic point of view.

Feeding of dried sweet orange ( Citrus sinensis ) peel on humoral immune response of broiler chickens Abstract Purpose An experiment was conducted to evaluate the effect of dried sweet orange (Citrus sinensis) peel (DCSP) on humoral immune response of broiler chickens. Methods Four hundred 1-day-old Ross 308 broilers were distributed according to a completely randomized design into five treatments with four replicates of 20 chicks each. The following five dietary treatments were applied: control group with 0% DCSP; diet containing 1.5% DCSP from 1 to 21 days of age (starter phase) and from 1 to 42 days of age, respectively; and diet containing 3% DCSP from 1 to 21 days of age (starter phase) and from 1 to 42 days of age, respectively. Results The DCSP treatments influenced positively total anti-SRBC and IgG titers on days 28 and 42, whereas no differences were found for IgM titer. The anti-NDV titers were not affected by diets; conversely, the anti-AIV titers were different among treatments. The anti-IBD titers were different on days 14 and 42 among diets, whereas anti-IBV titers were not influenced by treatments. Average white blood cell, heterophil, lymphocyte, and monocyte counts, as well as heterophil/lymphocyte (H/L) ratio, were different among treatments. Conclusion The findings suggested that the dietary inclusion of dried Citrus sinensis promoted some effects on the immune humoral response of chickens; however, these effects were not completely effective to protect birds from the main diseases.

Changes on soil structural stability after in natura and composted chicken manure application Abstract Purpose Many studies evaluate the effect of successive applications of chicken manure on soil attributes. In Brazil, the commercialization of this waste is common, implying on its sporadic use instead of many applications at the same area. The short-term effects of a single application of chicken manure and the role of its composting on soil structural stability are not fully understood. This study investigated application of in natura (uncomposted) and composted chicken manure on the structural stability of a Rhodic Ferralsol after a short period following single application. Methods The experiment was performed in a Rhodic Ferralsol in Londrina, Paraná. Brazil. We applied in natura and composted chicken manure at doses of 4.5, 9.0, 13.5, and 18.0 Mg ha−1 plus a control without application. Soil samples were collected after 185 days at the 0.0–20.0 cm layer for laboratorial analysis. Results The composting of chicken manure did not affect soil structural stability. Chicken manure did not alter water-dispersible clay \((\bar{x}=21.7\%),\) but increased the mean weight diameter of water-stable aggregates (MWD = 5.43 + 0.068 × dose) through the agglomeration of aggregates with 0.5–4 mm into 8–19 mm. Conclusion Even after a short period of 185 days, the application of chicken manure increases the structural stability of Rhodic Ferralsols and its composting, in the way performed by many farmers, is not associated with the improvement of soil structural stability in short-term. However, other advantages arise from the composting of the manure and need to be considered prior its use.