Commercial Mushroom Production Research Articles

Impact on Vitamin D2, Vitamin D4 and Agaritine in Agaricus bisporus Mushrooms after Artificial and Natural Solar UV Light Exposure.

Commercial mushroom production can expose mushrooms post-harvest to UV light for purposes of vitamin D2 enrichment by converting the naturally occurring provitamin D2 (ergosterol). The objectives of the present study were to artificially simulate solar UV-B doses occurring naturally in Central Europe and to investigate vitamin D2 and vitamin D4 production in sliced Agaricus bisporus (button mushrooms) and to analyse and compare the agaritine content of naturally and artificially UV-irradiated mushrooms. Agaritine was measured for safety aspects even though there is no rationale for a link between UV light exposure and agaritine content. The artificial UV-B dose of 0.53J/cm(2) raised the vitamin D2 content to significantly (P<0.001) higher levels of 67.1±9.9μg/g dry weight (DW) than sun exposure (3.9±0.8μg/g dry DW). We observed a positive correlation between vitamin D4 and vitamin D2 production (r(2)=0.96, P<0.001) after artificial UV irradiation, with vitamin D4 levels ranging from 0 to 20.9μg/g DW. The agaritine content varied widely but remained within normal ranges in all samples. Irrespective of the irradiation source, agaritine dropped dramatically in conjunction with all UV-B doses both artificial and natural solar, probably due to its known instability. The biological action of vitamin D from UV-exposed mushrooms reflects the activity of these two major vitamin D analogues (D2, D4). Vitamin D4 should be analysed and agaritine disregarded in future studies of UV-exposed mushrooms.

Prospects for Increasing Commercial Mushroom Production in Malaysia: Challenges and Opportunities

One of the benefits of mushroom cultivation is their potential contribution to a more sustainable and environmentally-friendly way of farming. Mushroom cultivation using an agricultural waste as a growing medium, and the subsequent use of spent substrate has high value for horticultural activity; organic fertilizer; and potential utilise for animal feeding. The value of mushroom to diets, coupled with reported medicinal properties, can also provide valuable additional new small and medium-scale business options. This study attempts to evaluate the mushroom industry prospects in Malaysia. It also explores issues and challenges facing the mushroom industry in Malaysia by using a critical analysis and SWOT analysis. The main challenges include poor supply and the increasing price of raw material, for example sawdust; the poor quality of mushroom spawn, and the threat of diseases and pest attack. Several strategies are discussed to potentially improve the productivity of mushroom cultivation in Malaysia. DOI: 10.5901/mjss.2016.v7n1s1p406

Camptotheca acuminata Decne residue after camptothecin extract as a substrate to produce mushroom spawn

Currently in China, no technically and economically viable methods exist to handle large quantities of Camptotheca acuminata Decne residue (CA residue) after camptothecin extract while there is a great demand for low cost alternatives to replace the cottonseed hull-based materials used in commercial mushroom culture. Hence, it is of importance for camptothecin extract factories and mushroom producers to explore the utilization of CA residue in mushroom industry. We conducted a research to study how partially or completely substituting traditional mushroom substrate by CA residue would influence the mycelial growth in mushroom spawn production. 5 mushroom strains from 4 species were used in the test, i.e., oyster mushroom (Pleurotus ostreatu) strains, Zayou No. 1 and Xide 33, needle mushroom (Flammulina velutipes) strain ChuanjinNo. 3, hairy wood ear (Auricularia polytricha) strain Huang Er No. 10, and shiitake (Lentinula edodes) strain Wuxiang. The nutrient element composition and heavy metal contents of CA residue were determined to ensure its safety and to determine its appropriate component in the substrate formulation for mushroom spawn production. The four substrate formulations (one control — CK, and three treatments, named, T1, T2, T3,) contained 0%, 40%, 79%, and 100% CA residue, respectively, to allow comparison of the fungal mycelial growth. The control (CK) was the popularly used formulation in Chinese commercial mushroom production, comprising of 73% cottonseed hulls, 10% sawdust, 15% wheat bran, 1% lime, 1% white sugar (percentage by weight). All mushroom spawns of the five strains in the four treatments were incubated under the same conditions. The results showed that mycelia of the five mushroom strains grew significantly faster on the substrates containing CA residue than on the substrate with no CA residue (CK). There were no significant differences in the mycelial growth rate among treatments containing CA residue for the two oyster mushrooms and the needle mushroom, but mycelial growth rate in treatments T2 and T3 was significantly higher than in treatment T1 for hairy wood ear and shiitake. The results suggest that CA residue can be used to culture oyster mushroom, needle mushroom, hairy wood ear, and shiitake spawn, and the medium containing CA residue can stimulate their mycelial growth. The commercial production of mushroom spawn using CA residue not only brings better economical benefits including lower cost to mushroom producers, but also reduces environmental pollution by providing a means to reduce dumping and piling of CA residue.

Transcription factor genes of Schizophyllum commune involved in regulation of mushroom formation

Mushrooms represent the most conspicuous structures of fungi. Their development is being studied in the model basidiomycete Schizophyllum commune. The genome of S. commune contains 472 genes encoding predicted transcription factors. Of these, fst3 and fst4 were shown to inhibit and induce mushroom development respectively. Here, we inactivated five additional transcription factor genes. This resulted in absence of mushroom development (in the case of deletion of bri1 and hom2), in arrested development at the stage of aggregate formation (in the case of c2h2) and in the formation of more but smaller mushrooms (in the case of hom1 and gat1). Moreover, strains in which hom2 and bri1 were inactivated formed symmetrical colonies instead of irregular colonies like the wild type. A genome-wide expression analysis identified several gene classes that were differentially expressed in the strains in which either hom2 or fst4 was inactivated. Among the genes that were downregulated in these strains were c2h2 and hom1. Based on these results, a regulatory model of mushroom development in S. commune is proposed. This model most likely also applies to other mushroom-forming fungi and will serve as a basis to understand mushroom formation in nature and to enable and improve commercial mushroom production.

DEVELOPMENTAL GENETIC ANALYSIS FOR CRUDE FIBER CONTENT AND CRUDE ASH CONTENT OF RAPESEED MEAL IN TWO DIFFERENT GROWING YEARS

Developmental genetic analyses method for diploid seed quantitative traits was used to determine the unconditional and conditional genetic main effects and genotype × environment interaction effects from embryo, cytoplasm and maternal genetic systems on crude fiber content (CFC) and crude ash content (CAC) of rapeseed meal in two growing years. The results suggested that the performance at most developmental times/stages for CFC and CAC was mainly affected by the genetic main effects. By using the conditional analysis method, for the different genetic systems, CFC and CAC were simultaneously controlled by the genetic effects from three genetic systems, especially for the maternal main effects. Also, the additive effects were more prominent at most developmental times/stages, and the improvement of both traits could be expected in earlier generation(s) in rapeseed breeding programs. The heritability analysis revealed that the maternal heritability was more prominent during seed development times, especially at maturity. Thus, it suggested that maternal plant selection could be utilized to reduce CFC and increase CAC in rapeseed meal breeding programs. The study further suggested Youcai 601 could be used for reducing CFC, while Huashuang 3 and Zhongyou 821 were suitable for increasing CAC in rapeseed, as evidenced from their predicted parent effects. PRACTICAL APPLICATIONS Rapeseed is an industrially and commercially important oilseed crop. For the oilseed industry, the meal remaining after oil extraction represents a product of a value equal to that of the oil itself. It represents a very valuable protein component of feed mixes that are, in turn, indispensable in modern monogastric animals raising for intensive production of meat, eggs and milk. In certain cases, the oilmeal is further processed to produce concentrates (with 50–60% of crude protein) or isolates (nearly pure protein) for use in human food. Rapeseed flours, protein concentrates and isolates are lower in protein but higher in crude fiber and ash contents than corresponding soybean products. Also, rapeseed or canola meal has been used as fermentation substrate, as an additive in compost for commercial button mushroom (Agaricus bisporus) production and also as substrate for xylanase production by Trichoderma reesei. Oilmeals are mainly valued for low fiber content, high protein content of good quality and absence or low presence of toxic and antinutritional compounds. One drawback of rapeseed meal is its higher crude fiber content, which results in lower digestible energy, especially for non-ruminants. Decreasing the crude fiber and improving the crude ash (an indicator of the mineral content) could increase the demand for rapeseed meal as a feed source for livestock.

Microbially induced diseases of Agaricus bisporus: biochemical mechanisms and impact on commercial mushroom production

The button mushroom, Agaricus bisporus (Lange) Imbach, the most common cultivated mushroom, is susceptible to a wide range of virus, bacterial, and fungal diseases. However, only some diseases were studied for the mechanisms involved in the host-microorganism interaction. This review deals with biochemical mechanisms related to cavity disease (Burkholderia gladioli) and to the interaction between A. bisporus and the causal agents responsible for the most severe diseases, namely the bacteria Pseudomonas tolaasii and Pseudomonas reactans and the fungi Trichoderma aggressivum and Lecanicillium fungicola.

The predatory mite Stratiolaelaps scimitus as a control agent of the fungus gnat Bradysia matogrossensis in commercial production of the mushroom Agaricus bisporus

We evaluated the potential effectiveness of the mite Stratiolaelaps scimitus (Womersley) in controlling populations of the sciarid fly Bradysia matogrossensis (Lane) in commercial production of the mushroom Agaricus bisporus (Lange). Two mushroom farm experimental tests were conducted: in the first, one of the treatments corresponded to two releases of the predator (immediately after inoculation of A. bisporus in the substrate and immediately after casing); in the second, one of the treatments corresponded to a single release of the predator (immediately after casing). In both cases, the contrasting treatment (control) represented the adoption of no measure to reduce the pest population. Pest population density was significantly lower, while yield of top quality mushroom was significantly higher in both predator release treatments than in the controls. Samples taken at the end of the tests suggested that the population density of S. scimitus increased in the mushroom bags during the course of the experiment. The results indicate that S. scimitus can effectively control B. matogrossensis in commercial mushroom production.

Biological control of Lycoriella ingenua (Diptera: Sciaridae) in commercial mushroom (Agaricus bisporus) cultivation: a comparison between Hypoaspis miles and Steinernema feltiae

Mushroom cultivation may be adversely affected by insect pests, including sciarids (Lycoriella spp.), which were previously controlled by application of chemical pesticides. However, owing to food safety and environmental concerns, availability of pesticides for use during mushroom cultivation has diminished. Consequently, it is imperative to investigate alternative control strategies, not reliant on chemical pesticides, which may be used in an integrated pest management system. Application of the predatory mite Hypoaspis miles Berlese to commercial mushroom-growing beds at the beginning of spawn run or just prior to casing (830 mites m(-2)) significantly reduced immature sciarids, Lycoriella ingenua (Dufour), in the growing substrate and also adult activity towards the conclusion of cropping. A trend towards lower sciarid emergence from substrates and reduced adult sciarid activity was observed following the application of Steinernema feltiae (Filipjev) (1.5 x 10(6) nematodes m(-2)) at casing. No significant treatment effects on mushroom yield were observed. However, contamination of the mushroom crop by adult sciarids increased in untreated controls. Application of H. miles required a 12-fold increase in labour when compared with application of S. feltiae. Contingent upon the development of an effective application system, H. miles has potential for the biological control of sciarids in commercial mushroom production.

Effect of Pseudomonas sp. P7014 on the growth of edible mushroom Pleurotus eryngii in bottle culture for commercial production

Addition of bacterial culture strain P7014 and its supernatant to the mushroom growing media resulted in mushroom mycelia run faster. Mycelial growth rate of Pleurotus eryngii was increased up to 1.6 fold and primordial formation was induced one day earlier. Moreover, it was supposed that addition of bacteria had beneficial applications for commercial mushroom production, which appreciably reduced total number of days for cultivation of about 5 ± 2 days compared with uninoculated, which took 55 ± 2 days.

Feasibility of using olive mill effluent (OME) as a wetting agent during the cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw

In this study, cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw substrate containing tap water and olive mill effluent (OME) mixture containing varying volume of OME was studied in order to investigate the feasibility of using OME as an alternative wetting agent and OME’s impact on some fundamental food quality characteristics of mushrooms. Time period for mycelial colonization, primordium initiation and first harvest were comparatively evaluated with the control group. It was shown that the use of OME and tap water mixture consisting of OME up to 25% volumetrically was possible for the purpose of commercial mushroom production. Experimental results obtained from substrate containing 25% OME mixture showed no statistically significant difference compared to control group. The negative effects of increasing volume of OME in the mixture were also indicated by bioefficiency, which was found to be 13.8% for substrates wetted with 100% OME, whereas bioefficiency was 53.6% for control group. Increasing volume of OME in the mixture resulted in deformation of fruit body shape, whereas no significant difference in food quality was observed due to the higher amount of OME. This work suggested that the use of OME up to 25% as moisturizer could be considered, especially for the locations having significant number of olive mills and mushroom producers, both as an environmentally friendly solution for the safe and ecological disposal of OME and a practical way for recovering OME’s economic value thereby.

The spectral specific responses of Lycoriella ingenua and Megaselia halterata during mushroom cultivation

The study reported examines the spectral specific responses of adult insect pests of mushroom (Agaricus bisporus (Lange) Imbach) cultivation to light traps and the potential for use of light trapping as a pest management tool within commercial mushroom production. Lycoriella ingenua (Dufour) (Diptera: Sciaridae) and Megaselia halterata (Wood) (Diptera: Phoridae) were the principal insect pests at the experimental site. Adult L. ingenua and M. halterata were positively phototactic and relatively high numbers were attracted to relatively low light emissions from light trap sources of differing wavelengths. Yellow sticky traps at a height of 1·7 m collected more flies of both species than traps located at crop height (0·6 m). Adult female L. ingenua were more numerous than males in all trap types suggesting that they were more active fliers than male counterparts. Numbers of females recorded in light traps greatly exceeded those in yellow sticky traps, indicating greater photo-responsiveness. Light wavelengths between 300–650 nm attracted greater numbers of adult L. ingenua than wavelengths exceeding 700 nm. This species was present throughout the year but was most abundant between May and December. Adult M. halterata were less numerous than adult L. ingenua in all trap types and particularly on yellow sticky traps at crop level. The lower disparity between numbers of adult M. halterata on light traps and yellow sticky traps suggests that adults of this species are not as photosensitive as adult L. ingenua. The observed response of adult M. halterata to light sources of different wavelengths was variable within the range 300–&gt;700 nm. Adult M. halterata were most abundant between June and November.

Bioaugmentation of tar‐contaminated soils under field conditions using Pleurotus ostreatus refuse from commercial mushroom production

The influence of the white rot fungus Pleurotus ostreatus on the degradation of selected poly- and heterocyclic aromatic hydrocarbons (referred to as polycyclic aromatic hydrocarbons [PAHs]) in soil was investigated under field conditions representing the Northern temperate zone. Pleurotus ostreatus was added to two contaminated soils in the form of homogenized refuse from the commercial production of fungus. The soils were collected from a former shipyard (the B&W soil) and underneath a former coal tar storage at an old asphalt factory in Denmark (the Ringe soil). Treatments (control, soil mixed with autoclaved sawdust medium, and soil mixed with P. ostreatus refuse) were set up in triplicate in concrete cylinders (height, 50 cm; diameter, 60 cm). The activity of P. ostreatus was measured as laccase activity and phenanthrene (PHE)- and pyrene (PYR)-degrading bacteria were enumerated. Twenty-one different PAHs were quantified. After nine weeks the concentrations of the 3-, 4-, 5-, and 6-ring PAHs in the Ringe soil were reduced by 78, 41, and 4%, respectively. These reductions corresponded with high initial laccase activity, a decrease in pH caused by the fungus, and an increase in the number of PHE- and PYR-degrading bacteria. No significant PAH degradation was observed in the B&W soil. Reasons for the difference in performance of P. ostreatus in the two soils are discussed in terms of soil histories and bioavailability. The use of P. ostreatus refuse holds promising potential for bioremediation purposes.

IN–VESSEL PROCESSING OF SPENT MUSHROOM SUBSTRATE FOR ODOR CONTROL

Spent mushroom substrate (SMS) was processed in an aerated floor vessel and compared to SMS processed byconventional windrow methodology. The aerated floor vessel design provided portability and ease of use. Three trials wererun using SMS obtained directly from commercial mushroom production operations. Temperature and oxygen levels in theaerated and windrow SMS were monitored regularly. Odors were assessed on a weekly or biweekly schedule, botholfactometrically using human panels and quantitatively using gas chromatography with flame photometric detection(GC/FPD). Olfactometric assessment showed that the odors were significantly reduced by aeration in terms of intensity andpleasantness ratings. GC/FPD assessments also demonstrated that aeration consistently reduced sulfur compound levels.

A protocol for evaluation of the role of disinfectants in limiting pathogens and weed moulds in commercial mushroom production.

In vitro and in vivo evaluations of the effects of three commercial disinfectants on isolates of Trichoderma harzianum Rifai and Cladobotryum dendroides (Bull) W Gams & Hoozemans were combined in the development of methodologies for realistic assessment of disinfectant performance. 'Environ' and 'Purogene' incorporated into agar media at 50 mg AI litre-1 were effective in totally preventing the mycelial growth of T harzianum and C dendroides isolates, whereas with 'Sudol' a concentration of 500 mg AI litre-1 was required. Evaluation of a model in vivo system was combined with observations on the fungicidal effects of disinfectants. Spore suspensions of T harzianum (Th1), T harzianum (Th2) and C dendroides prepared from culture washings with sterilised distilled water were used as contaminating inoculum. Environ, Sudol and Purogene in aqueous solutions at 1000 mg AI litre-1 were sprayed onto these building structure surfaces before or after artificial contamination with spore suspensions. Re-isolation from surfaces was carried out using agar swabs, which were prepared in visking tubing, applied to treated surfaces and incubated at 25 degrees C for 24, 48, 72 or 96 h. Environ and Purogene were more effective than Sudol in limiting the recovery of Trichoderma spp and C dendroides. All three disinfectants applied 12 h after artificial contamination onto wood, concrete or glazed surfaces were able to reduce the recovery of these isolates more effectively than when they were applied 12 h before artificial contamination. Greater persistence of contamination was noted on the rougher surfaces (wood and concrete) than on the smoother glazed surface. It was concluded in this in vivo evaluation that, in many cases, the protection achieved by the physical nature of the smooth glazed tile surfaces was equivalent to that available from the application of disinfectants, thus highlighting the attention needed to the nature of building surfaces in the structures used in the mushroom industry. The artificial contamination and re-isolation techniques allowed significant comparison between disinfectant materials, timings and surface types. In the in vivo experiments using a single standardised test concentration, the relative fungicidal effects of the disinfectants, which varied in the complexity of their active ingredients, were better discriminated than the effects observed in vitro, although the general trend was similar.

Identification of Bacteria in Mushroom Compost Using Ribosomal RNA Sequence

Microorganisms in mushroom substrate play important roles in commercial mushroom production. We have initiated the characterization of microorganisms in Phase II compost using sequences of genes encoding small subunit ribosomal RNA (rDNA). A specific area of rDNA was amplified from individually cultured organisms as well as from total DNA extracted from the compost sample by polymerase chain reaction. Thirteen rDNA fragments sequenced in this study corresponded to 12 different strains representing three divisions of bacteria. All of these strains, except Bacillus licheniformis, have not previously been identified through rDNA sequencing, suggesting that mushroom compost contains many novel organisms.

Application of fungal substrate from commercial mushroom production — Pleuorotus ostreatus — for bioremediation of creosote contaminated soil

Degradation of polycyclic aromatic hydrocarbons in aged-creosote contaminated soil by applying spent mushroom compost, oyster mushroom, was studied in medium sized polyethylene columns. Two different commercial sources of inoculum were compared, and the effect of organizing soil and substrate in layers or mixing it together was investigated. Degradation of 3-ring compounds were similar for the two fungal inoculums. For the hard degradable PAHs (4- and 5-ring) there was a significant difference. The 4- and 5-ring PAHs were degraded better when soil and fungal substrate were homogenized rather than layered. Fish oil added to spent mushroom compost and mixed with creosote contaminated soil gave best degradation of PAHs. This treatment, incubated for 7 weeks at ambient temperature, resulted in the following removal: 86% of total 16 PAHs, 89% of 3-ring PAHs, 87% of 4-ring PAHs and 48% of 5-ring PAHs.

The use of chemicals, antagonists, repellents and physical barriers for the control of Lycoriella auripila (Diptera: Sciaridae), a pest of the cultivated mushroom Agaricus bisporus

SummaryThe sciarid, Lycoriella auripila, is a serious pest of commercial mushroom production. A series of trials demonstrated that the use of early, specifically‐targeted, treatments of insecticides and/or antagonists and repellents, which distance treatment time from crop harvest, have the potential to play a useful part in the control of initial and subsequent generations of this pest. Of the treatments examined, those involving a drench treatment of the compost at filling (before pasteurisation) proved to be the most effective. Cyromazine and diflubenzuron were the most active insecticides tested, with cyromazine achieving a superior level of control of the initial infestation. Repellents and antifeedants were also effective, with calcium oxalate and sinapic acid both achieving about 50% control when applied at filling. Treatments applied later during the production cycle, unless in combination with a treatment at filling, were progressively less effective at controlling both the initial sciarid infestation and later generations of larvae. Multiple treatments caused greater reductions in fly populations than did the single treatments and continued to do so throughout the cropping cycle, the greatest reduction in the initial generation (79%) occurring with a triple treatment of cyromazine. With the exception of some diflubenzuron treatments, those that were effective resulted in increases in yield. The use of a physical paper barrier caused significant increases in both fly numbers and total yield.

Identification of exopolysaccharides produced by fluorescent pseudomonads associated with commercial mushroom (Agaricus bisporus) production.

The acidic exopolysaccharides (EPSs) from 63 strains of mushroom production-associated fluorescent pseudomonads which were mucoid on Pseudomonas agar F medium (PAF) were isolated, partially purified, and characterized. The strains were originally isolated from discolored lesion which developed postharvest on mushroom (Agaricus bisporus) caps or from commercial lots of mushroom casing medium. An acidic galactoglucan, previously named marginalan, was produced by mucoid strains of the saprophyte Pseudomonas putida and the majority of mucoid strains of saprophytic P. fluorescens (biovars III and V) isolated from casing medium. One biovar II strain (J1) of P. fluorescens produced alginate, a copolymer of mannuronic and guluronic acids, and one strain (H13) produced an apparently unique EPS containing neutral and amino sugars. Of 10 strains of the pathogen "P. gingeri," the causal agent of mushroom ginger blotch, 8 gave mucoid growth on PAF. The "P. gingeri" EPS also was unique in containing both neutral sugar and glucuronic acid. Mucoid, weakly virulent strains of "P. reactans" produced either alginate or marginalan. All 10 strains of the pathogen P. tolaasii, the causal agent of brown blotch of mushrooms were nonnmucoid on PAF. Production of EPS by these 10 strains plus the 2 nonmucoid strains of "P. gingeri" also was negative on several additional solid media as well as in two broth media tested. The results support our previous studies indicating that fluorescent pseudomonads are a rich source of novel EPSs.

An algorithm for locating mushrooms in a growing bed

Robotic harvesting systems for commercial mushroom production will require image guidance. This paper describes an algorithm which will identify the size and position of individual mushrooms in the growing bed. The algorithm uses knowledge of the shape of the mushroom to track around the outline in the grey-level image.

Airborne allergenic microorganisms associated with mushroom cultivation

Abstract Exposure to microorganisms, including thermophilic actinomycetes and fungal spores, and to airborne dust produced during compost production and mushroom picking may cause work-related respiratory symptoms. Previous studies have implicated Thermoactinomyces vulgaris and Faenia rectivirgula, the aetiological agents in farmer's lung disease, as causes of these symptoms but these species have been rare in aerobiological studies of mushroom farms. As part of a study of the respiratory health of the exposed workers, we carried out an aerobiological survey of all the stages of commercial mushroom production. Samples of viable airborne microorganisms were collected at a farm from eight locations on two occasions using Andersen cascade impactors. Large numbers of airborne thermophilic actinomycetes, yielding > 106 colony-forming units (cfu) m−3 air sampled, were associated with compost handling. These were predominantly Thermomonospora spp., while Thermoactinomyces spp. and Faenia rectivirgula were few. B...