Compost Formulations Research Articles

Yield of four Agaricus bisporus strains in three compost formulations and chemical composition analyses of the mushrooms

Three compost formulations, consisting of two varieties of Cynodom dactylon (L.) Pers. (Coast-cross and Tyfton) and oat (Avena sativa) straw were tested for the cultivation of A. bisporus strains ABI-01/01, ABI-04/02, ABI-05/03, and ABI-06/04. A completely randomized experimental design in a factorial scheme was adopted, with 12 treatments (4 A. bisporus strains × 3 types of compost) and 8 replicates. Each experimental unit corresponded to one box containing 12 12.5 kg fresh wet compost. The data were submitted to analysis of variance and the means were compared by Tukey test. According to the results, productivity of mushrooms was influenced by strain and/or compost type. It was also verified that crude protein, ash, and crude fiber contents in the mushroom varied with A. bisporus strain and straw used in the formulation of the compost.

Yield of four Agaricus bisporus strains in three compost formulations and chemical composition analyses of the mushrooms.

Three compost formulations, consisting of two varieties of Cynodom dactylon (L.) Pers. (Coast-cross and Tyfton) and oat (Avena sativa) straw were tested for the cultivation of A. bisporus strains ABI-01/01, ABI-04/02, ABI-05/03, and ABI-06/04. A completely randomized experimental design in a factorial scheme was adopted, with 12 treatments (4 A. bisporus strains × 3 types of compost) and 8 replicates. Each experimental unit corresponded to one box containing 12 – 12.5 kg fresh wet compost. The data were submitted to analysis of variance and the means were compared by Tukey test. According to the results, productivity of mushrooms was influenced by strain and/or compost type. It was also verified that crude protein, ash, and crude fiber contents in the mushroom varied with A. bisporus strain and straw used in the formulation of the compost.

A novel challenge test incorporating irradiation (60Co) of compost sub-samples to validate thermal lethality towards pathogenic bacteria

Maturing compost heaps normally attaining temperatures ranging from 55 to 65°C is generally regarded to conform to recommended biological risks and sanitation standards for composts stipulated by either EU or US-EPA. Composted products derived from animal sources are further required by EU biohazard safety regulatory legislation that such composts either attain 70°C for over 3h during maturation or via treatment at 70°C for 1h before being considered for dispensation on land. The setting of the upper limit of thermal lethality at 70°C/1h for achieving biosecurity of the animal waste composted products (e.g. pelleted fertilizer formulations) is not properly substantiated by specific validation tests, comprising a ‘wipe-out’ step (usually via autoclaving) followed by inoculation of a prescribed bacterium, exposure to 70°C/1h and the lethality determined. Pelleted formulations of composts are not amenable for wet methods (autoclaving) for wipe-out sterilization step as this is detrimental to the pellet and compromises sample integrity. This study describes a laboratory method involving the employment of (60Co) irradiation ‘wipe-out’ step to: (a) compost sub-samples drawn from compost formulation heaps and (b) pelleted products derived from composted animal products while determining the thermal lethality of a given time/temperature (70°C/1h) treatment process and by challenging the irradiated sample (not just with one bacterium but), out with 10 potential food-poisoning organisms from the bacterial genera (Campylobacter, Escherichia, Listeria, Salmonella, Yersinia) frequently detected in pig and poultry farm wastes. This challenge test on compost sub-samples can be a useful intervention ploy for ‘inspection and validation’ technique for composters during the compost maturity process, whose attainment of temperatures of 55–65°C is presumed sufficient for attainment of sanitation. Stringent measures are further required by law for composted products arising from rural industrialists producing pelleted fertilizers from re-composted animal agriculture wastes comprising pig slurry solids, poultry litter and spent mushroom compost, which carry residual food-borne pathogens with implications to the food chain including humans. Environmentally, sustainable means of recycling farm wastes require that final composted products are free of pathogens in compliance with environmental safety legislation before their release to the market. This test developed provides a science-based risk characterization tool for sustainably managing environmental safety by ‘validating’ thermal lethality of a given composting process or their derivatives achieved without compromising the sample integrity or ambiguity attached to microbiological validation involving steam sterilization or autoclaving procedures and helps audit the resurgent bacterial populations from surviving non-pathogenic organisms in the end-products of animal waste compost formulations.

Chemical changes under aerobic composting and nutrient supplying potential of banana residue compost

AbstractIn anticipation of the Philippines being a major producer of organic bananas, this study was conducted to provide a quantitative basis for certain practices in organic farming. The nutrient supplying capacity of banana residues in combination with leguminous materials and chicken manure was investigated in composting studies. Changes in the chemical composition of ten formulations of banana residue-based compost involving leguminous plants (Sesbania rostrata, Flemingia macrophylla, Arachis hypogea) and chicken manure were analyzed periodically during a composting period of 16 weeks. Results showed that combinations of banana residues (BnR) and chicken manure or leguminous plants were highly decomposed compared to untreated BnR. The use of leguminous plants and/or chicken manure enhanced the composting process significantly compared to the effect of Bioquick. The compost piles were characterized by increases in pH, total N and total P, and decreases in total K, total carbon and C/N ratio with time. Notably, BnR+chicken manure attained a C/N ratio of 15 at 4 weeks, while the BnR+leguminous materials reached such a low C/N ratio at 8–16 weeks. An incubation study was conducted under greenhouse conditions for 24 weeks. It was designed to follow the dynamics of nitrogen (N), phosphorus (P) and potassium (K) availability in two clay soils (Antipolo and Lipa) amended with five compost formulations (BnR alone, BnR+Sesbania prunings, BnR+Flemingia prunings, BnR+peanut stover and BnR+chicken manure) and with uncomposted banana residue at an application rate of 20 Mg ha−1. Results showed that net N mineralization occurred in soils amended with BnR+chicken manure and BnR+leguminous materials, which had C/N ratios ranging from 12 to 16. Net N immobilization during the earlier period of incubation was observed in uncomposted and composted banana residues with a C/N ratio of 68 and 24, respectively. Significantly higher net P mineralization was obtained only in soils amended with BnR+chicken manure. An abrupt increase in exchangeable K was observed in all treatments 2 weeks after the incorporation of organic residues. Higher available K in pure BnR treatments (uncomposted or composted) exhibits the inherently high K content of banana residues.

The Effects of Poultry Manure Based Formulations on Odor Generation During Phase I Mushroom Composting

Bioreactors were designed and built to study the effects of Phase I mushroom compost formulation on odor production. Three different poultry manure levels: 0x, 1x and 2x [0 %, 5.1 %, and 11.0 % dry weight basis, respectively] were used in compost formulations to determine if poultry manure influenced odor production. Air samples were collected for sensory odor measurements twice during the eight-day Phase I composting period (day one and day six) for three replicates. Phase I compost odors were quantified by a trained odor panel. Odor intensity and pleasantness ratings were significantly different on day one, however, neither the intensity nor the pleasantness was significantly different on day six. The amount of poultry manure used in formulation had no significant effect on total mushroom yield.

Composted recycled organic matter suppresses soil-borne diseases of field crops.

• Suppression of soil-borne diseases of horticultural crops by composts has been attributed to the activities of antagonistic microorganisms. The potential for abiotic disease suppression in field-grown crops was explored using glasshouse-based bio-assays for five pathogens of agricultural crops and eight formulations of recycled organic matter compost. • The effects of compost formulation and postmaturation processing were investigated by comparing disease severity on recycled organic matter composts with a commercial seedling compost. Comparisons were made within native and autoclaved series of composts. Autoclaving perturbed compost chemistry without the addition of other materials. • The severity of autoclaving-induced changes to compost chemistry were related to formulation and processing issues. Extractable carbon content, nitrate-N content and pH all contributed to the suppressive capacity of recycled organic matter composts. There may also be a biotic component to the suppression observed. • For each pathogen the influential chemical characteristics of suppressive composts were the same as those identified for soils in other studies. There is potential for the suppressive capacity of recycled organic matter composts to be improved.

Evaluation of Composts for Suppression of Dollar Spot (Sclerotinia homoeocarpa) of Turfgrass.

The use of composts in turfgrass disease management allows for a reduction in pesticide use in chemical control practices. Disease suppressive properties of composts rely on a number of factors including microbial activity, microbial population dynamics, nutrient concentrations, and other associated chemical and physical factors. Five composts were evaluated for suppression of dollar spot caused by Sclerotinia homoeocarpa. The dollar spot disease suppressive properties of selected compost formulations prepared in different years was evaluated. A third objective was to examine the effects of storage of compost (1 year) on the suppression of dollar spot. Field experiments were conducted in 1998 with compost prepared in 1997 to 1998. Applications of compost every 3 weeks throughout the season suppressed dollar spot of turf to levels not significantly different than applications of chlorothalonil fungicide applied at the manufacturer's lowest recommended preventative rate of 38.4 ml a.i./100 m2 every 2 weeks (P = 0.05). Single applications of composts at the start of the 1998 season were not effective in reducing disease. Field experiments in 1999 evaluated batches of two selected compost formulations, one batch produced in 1998 to 1999, another stored since production in 1997 to 1998. Composts were effective in suppressing disease to levels not significantly different than the fungicide controls, which showed up to 33% disease in 1998 and up to 31% disease in 1999 (P = 0.05). Storage of composts for up to 1 year did not affect their ability to reduce dollar spot severity (P = 0.05). The use of composts as plant disease suppressants is not likely to replace the use of commercial fungicides in dollar spot management. However, multiple applications of compost may reduce incidence and severity of dollar spot to levels at which chemical control may be reduced or eliminated for a significant portion of the season.

Response of Four Container Grown Woody Ornamentals to Immature Composted Media Derived from Waxed Corrugated Cardboard

Four containerized deciduous ornamental shrubs [deutzia (Deutzia gracilis L.), silverleaf dogwood (Cornus alba ‘Elegantissima’), red-osier dogwood (Cornus sericea L.), and ninebark (Physocarpus opulifolius L.)] were grown during each of two separate growing seasons using 12 different immature (nonaged) composts as media (year one, 12 weeks from start of windrowing; year two, 16-weeks) and also two control nursery mixes (100 percent ground pine bark; and 80:15:5 by volume of pine bark:sphagnum peat:top soil). The compost formulations (volume basis) consisted of spent mushroom substrate (50 percent), waxed corrugated cardboard, 0 percent, 25 percent, or 50 percent), and/or pulverized wood wastes (50 percent, 25 percent, and 0 percent). Supplemental N was added to some composts as poultry manure (18 kg·m−3), soybean wastes (24·kg·m−3), or both at the same application rates. Despite the immaturity of the compost media and the presence of high initial contents of soluble salts primarily from the spent mushroom substrate (EC ≤6.4 dS·m−1, 1:1 v/v medium:water extracts), the top dry weight (averaged over two seasons) of each of the four species grown in compost media, regardless of waxed corrugated cardboard (WCC) level, exceeded that obtained in 100 percent pine bark. Compared with the 0 percent WCC compost, plants of all four species grew better in 25 percent and/or 50 percent WCC compost media and growth in these treatments was more (silverleaf dogwood), similar (deutzia and red-osier dogwood), or less than (ninebark) that in the 80:15:5 nursery mix. Rapid leaching of the potentially toxic soluble salts from the containerized compost media within days after planting minimized any adverse effects on the plants. There was no difference in foliar concentrations of N, P, K, Ca, Mg, Fe, Mn, and Zn due to WCC level, or to the N supplements which had little or no effect on growth. The foliar contents of heavy metals (Cu, Ni, Cr, Cd, Co, and Pb) were low and/or below detection limits.

Button mushroom production in synthetic compost derived from agricultural wastes

Abstract To assist a local button mushroom production industry — in which pre-spawned, pre-packaged synthetic compost was sold to satellite growers — we evaluated various processing parameters, some of which were unique to this type of operation. Corn/oat screenings and urea effectively replaced soybean meal in compost formulations, resulting in higher yields at a lower cost. Sorghum-based spawn contained more inoculum particles than rye-based spawn and, consequently, permitted faster compost colonization. Likewise, the use of higher spawning rates (227–340 g spawn/30 kg compost) resulted in faster colonization. Yield reductions due to improper picking and watering by inexperienced workers was minimized by applying thicker casing soil layers (4·6–5·6 cm); however, this caused mushroom initiation under the casing surface and thereby increased the ratio of dirty mushrooms. Buried perforated tubing was not effective in improving either mushroom yields or quality, as has been demonstrated for porous tubing. A water application rate of 1 liter/box/day appeared sufficient to maintain an adequate moisture reservoir in the casing layer. And finally, to obtain highest yields, the cardboard/plastic bottoms of compost boxes should be perforated to create approximately 1% open space. This allowed sufficient gaseous exchange without drying the compost.

Substrate usage and odours in mushroom composting

Odour problems associated with producing a composted substrate for mushroom culture were considered at 9 Australian farms, in relation to composting batch recipes. Effects of usage of nutrient rich composting activators were evaluated using nitrogen (N) concentration ratios (%) and a novel ratio, the C/A ratio as indicators of compost nutritional status. The CIA ratio segregated composting ingredients into nutritional classes. Both % N and the C/A ratio showed that excess nutrient usage was positively correlated with odours. Both correlations were significant at P= 0.01. Final % N, however, did not increase with higher initial % N values. This investigation indicates that reducing excessive initial concentrations of available nutrients in compost formulations can reduce odours, while not necessarily reducing compost quality in terms of final N level.