Comparison of the changes in mushroom (Agaricus bisporus) compost during windrow and bunker stages of phase I and II

The changes in thermophilic fungi and biochemical characteristics, during windrow and bunker stages of phase I and phase II composts, were compared in this investigation. Composts prepared by the two phase I systems differed in a number of key parameters including mean straw length, population of Scytalidium thermophilum, dry matter, conductivity, nitrogen dry matter, ammonia, fibre content and ash. S. thermophilum populations in phase I composts were significantly higher in windrow compared to bunker‐composted materials as a result of the larger high temperature (65‐80°C) core in bunker treatment, which inhibited microbial activity. Assessment of the composts for loss of matter during composting has revealed that the bunker system can conserve fresh matter better than the windrow production system, possibly due to lower microbial activities during bunker composting. The productivity of the phase II composts prepared from windrow and bunker systems was compared in trials using commercial growers.     

Effects of the paedogenetic mushroom cecid, Heteropeza pygmaea (Diptera:Cecidomyiidae) on cropping of the cultivated mushroom (Agaricus bisporus)

When introduced into a mushroom crop at rates of 2, 20 or 200 larvae/tray (0.56 m²), the mushroom cecid, Heteropeza pygmaea, caused significant reductions in both yield and number of mushrooms in relation to the infestation level. The reductions were greater when the larvae were introduced at spawning rather than at casing. The yield and number of infested (unmarketable) mushrooms increased significantly in relation to the initial infestation level. Just two H. pygmaea larvae, introduced at spawning, resulted in cecid populations that caused a 12% loss in total yield in addition to a 7% loss due to spoilage. Loss assessment in the future, therefore, should take into account both yield suppression and spoilage. There was little effect of cecid infestation on flush timing and mushroom size was only affected in the fourth flush, when a significant reduction (27%) was shown at the highest infestation rate at spawning.     

Comparison of the effect of two types of whole mushroom (Agaricus bisporus) powders on intestinal fermentation in rats

The effects of two types of mushroom (Agaricus bisporus; white, WM; brown, BM) powders on intestinal fermentation in rats were investigated in terms of the physical characteristics of animals and by bacterial and HPLC analyses of cecal contents. Short-chain fatty acid levels were found to be significantly higher in the WM group than in the BM and the control (CN) groups; coliform bacteria levels in the BM group were significantly lower than those in the CN group, with the WM group inducing an apparent but insignificant decrease in coliforms. Anaerobe levels in the WM group were significantly higher than those in the CN group and, compared with the CN group, the BM and WM groups exhibited significantly increased feces weight and cecum weight, respectively. These results indicate that the mushroom powders, and in particular the WM powder, have beneficial effects on the intestinal environment in rats.     

Use of molecular markers to differentiate between commercial strains of the button mushroom Agaricus bisporus

Agaricus bisporus is an edible basidiomycete cultivated industrially for food production. Different spawn and mushroom producers use genetically related A. bisporus strains frequently marketed as different products. In this paper we show that the use of suitable molecular markers reveals the high level of genetic homology of commercial strains of A. bisporus, and allows, at the same time, to distinguish between them. In the course of this work, a molecular marker potentially linked to the agronomic character 'mushroom weight' has been identified by bulked segregant analysis.     

伊朗Karaj地区双孢蘑菇上的螨类调查（英文）

2004年春季至2006年夏季期间,调查了伊朗Karaj地区双孢蘑菇上的螨类,发现了3目9科17种食菌性、捕食性和腐食性螨类,包括：光滑巨螯螨Macrocheles glaber (Müller),粪巨螯螨Macrocheles merdarius (Berlese),近褐巨螯螨Macrocheles subbadius(Berlese),甲虫寄螨Parasitus coleoptratorum （Linnaeus）,粪堆寄螨Parasitus fimetorum （Berlese）,乳突寄螨Parasitus mammillatus (Berlese),Sancassania rodionovi Zachvatkin,腐食酪螨Tyrophagus putrescentiae (Schrank),Uroobovella fimicola (Berlese),Ameroseius fungicolus^* Masan,Pediculaster kneeboni^* Wicht,Pediculaster flechtmanni^* Wicht,Scutacarus longitarsus (Berlese),Dendrolaelaps multidentatus^* Masan,柴特北绥螨Arctoseius cetratus (Sellnick),Lasioseius sugawarai^* Ehara和Ameroseius plumigera Oudemans。其中有“*”号标记的6个种为伊朗新纪录种,12个种为在蘑菇上首次发现。     

环境因子对双孢蘑菇损伤敏感性的影响（英文）

在机械损伤过程中,白色双孢蘑菇极易被损伤并迅速褐变,使得机械采收的鲜菇质量低下,并且影响机械采收技术的应用和发展。机械采收双孢蘑菇的褐变程度(损伤敏感性)受栽培环境条件的影响。本文应用因子设计分析的方式研究多个因子对双孢蘑菇机械损伤敏感性的影响。以4个菌株为材料测试3个环境因子对双孢蘑菇损伤敏感性的影响,即覆土的厚度(分为2.5cm和5cm两个水平),覆土的湿度(分为干覆土和正常覆土两个水平),以及菇房内的相对湿度(分为80%和87%两个水平)。目的是找出能够在不敏感菌株和敏感菌株间产生最大敏感性差异的环境条件,由此得到的环境条件将应用到后续的群体分离分析中以得到最大的敏感性变异率。根据方差分析结果得出基因型(菌株)和覆土厚度是影响损伤敏感性的显著性因子,因子间相互作用显著。能够在不敏感菌株和敏感菌株间产生最大的损伤敏感性差异的环境条件为正常湿度的5cm厚覆土材料和87%的菇房内相对湿度。     

Resource allocation ability of wild isolates of Agaricus bisporus on conventional mushroom compost

Abstract: Twenty-one wild isolates from two distinct sites and six cultivated strains of Agaricus bisporus were cultivated on a conventional mushroom compost. Their degradative abilities were studied by measuring 12 extracellular enzyme activities produced during mycelial growth. Differences in production of enzyme activities and in compost colonisation were observed between the three groups of strains and within each group. They were used to define the mechanisms of resource allocation in mushroom compost. The ability to grow and produce sporophores on mushroom compost appeared to be linked with the production of a balanced pool of enzymes including moderate levels of polysaccharidases active on straw cell walls and of enzymes able to degrade microbial biomass and microbial products.     

Comparative effects of Steinernema feltiae (Nematoda: Steinernematidae) and insecticides on yield and cropping of the mushroom Agaricus bisporus

In a mushroom crop (Agaricus bisporus) affected by a very low level of sciarid fly (Lycoriella auripila) infestation, the effects of an indigenous isolate of insect-parasitic nematode (Steinernema feltiae) and of two commonly used insecticides (diazinon and diflubenzuron) were studied. When compared with untreated plots, nematodes applied to the casing had no adverse effects on mushroom yields whereas insecticides decreased yields. At a rate of 3 × 10⁶ infective juveniles per tray (surface area = 0.56 m²), S. feltiae elicited increases of 28.5% and 19% in the mean total numbers and weights of mushrooms respectively. Treatment only with diflubenzuron resulted in 14.6% and 6% reductions in mean total numbers and weights of mushrooms, respectively; treatment with both diazinon and diflubenzuron caused 18.5% and 9.4% losses. Application of nematodes generally reduced the mean weight per mushroom whereas insecticides increased it; nematodes delayed the onset of mushroom production (first flush) whereas diflubenzuron delayed the third and fourth flushes. Nematode contamination of sporophores was minimal when S. feltiae was applied at casing. Although their numbers declined with time, the nematodes persisted, in the casing layer, throughout the cropping period of seven weeks. It is concluded that yield benefits associated with nematode application can result mainly from nematode effects on A. bisporus and not solely from suppression of a damaging pest population.     

Comparative effects of three insect growth regulator insecticides and a dipteran-active strain of Bacillus thuringiensis on cropping of the cultivated mushroom Agaricus bisporus

Three insect growth regulator insecticides and an entomopathogenic strain of Bacillus thuringiensis (GC327), products effective against the mushroom sciarid, Lycoriella auripila, were compared for their effect on mushroom cropping. Cyromazine and diflubenzuron were applied as a surface drench to mushroom compost before or after pasteurisation (at filling or spawning, respectively); admixed into casing material (at casing); or at a combination of these times. Hexaflumuron and GC327 were applied only at filling and casing, respectively. The presence of the target pest, L. auripila, had no effect on treatment trends, although it was accounted for in the analysis by use of a yield model. The trial was notable for the disparate effects that cyromazine and diflubenzuron casing treatments had on mushroom cropping. Cyromazine treatments that included application at casing resulted in increases in yield, compared to the untreated control whereas, with diflubenzuron, the opposite was true, with treatment at casing alone causing the greatest reduction overall (10%). GC327 applied at casing was also conspicuous for giving a 13% increase in yield. Treating the crop at casing with either cyromazine or GC327, therefore, resulted in a 15% or 24% increase in yield, respectively, compared to a similar treatment with diflubenzuron. Hexaflumuron applied at filling caused increases in yield compared to application of cyromazine at filling and cyromazine or diflubenzuron at spawning. There were also effects on crop timing. The addition of a cyromazine casing treatment normally caused the distinct flushes of mushrooms to be produced significantly earlier than the untreated control (up to 2.5 days), as did GC327. With diflubenzuron, the earlier flushes were only produced by those treatments that did not include a casing application. The combinations that included a casing treatment with diflubenzuron initially produced mushroom flushes earlier than the untreated control. They became either synchronous with the control or they were delayed. From the crop tolerance perspective, therefore, cyromazine and GC327 would be the sciarid control products of choice for a commercial mushroom grower.     

The comparative effects of three formulations of diazinon on cropping of a hybrid and a non-hybrid strain of the cultivated mushroom Agaricus bisporus

Three formulations of diazinon: flowable granules (FG); wettable powder (WP); and emulsifiable concentration (EC), which are used for the control of mushroom pests, were compared for toxicity towards a hybrid and non-hybrid strain of the cultivated mushroom, Agaricus bisporus. With all formulations, yield and number of mushrooms were reduced according to dosage (linear trend). The EC was the most toxic and persistent formulation – equally so to both mushroom strains – and produced the most severe responses in all the parameters considered. The WP was the least toxic formulation. The hybrid strain was more susceptible to diazinon than the non-hybrid, but not markedly so.     

全球野生双孢蘑菇种质资源的研究现状

双孢蘑菇 (Agaricusbisporus)是世界最重要的人工栽培的食用菌 ,近 10a来对其野生种质资源的研究在广泛地进行 ,试从野生双孢蘑菇的自然居群的分布 ,遗传变异、交配类型和生活史等方面对全球野生双孢蘑菇种质资源的研究现状进行综述。     

Effects of Caenorhabditis elegans (Nematoda: Rhabditidae) on yield and quality of the cultivated mushroom Agaricus bisporus

Thirteen species of saprobic rhabditid nematodes (11 genera) were identified from samples of compost and casing material collected from mushroom farms in the British Isles. Caenorhabditis elegans, the most frequently found saprobe, was mass-produced monoxenically and its effects on the cultivated mushroom, Agaricus bisporus (strain U3) were studied. C. elegans did not multiply in well-prepared, pasteurised, spawned compost, whereas casing material proved to be a highly suitable environment for its reproduction. An initial casing inoculum of 10⁶ nematodes/crate of compost (7.5 kg), caused a significant reduction in mushroom yield. Losses in total mushroom yields of 11%, 20% and 26% were caused by initial inoculum rates of 10⁶, 10⁷and 2 × 10⁷ nematodes/crate, respectively. Yields were negatively correlated with the initial nematode inoculation level and regression equations were derived. The nematode treatments caused fewer mushrooms to be produced and an absence of the usual distinctive flushing patterns. C. elegans caused considerable deterioration in mushroom quality and characteristic distortion of mushrooms. Individual sporophores were mis-shapen, notched and had brown or violet coloured grills. Up to 3.8%, 6.7% and 10.8% of total weight and 3.5%, 5.4% and 8% of total numbers of mushrooms were distorted at the three highest nematode inoculum rates tested. Weights and numbers of distorted mushrooms were positively correlated with the initial nematode population. C. elegans commonly colonised sporophores.     

不同地区双孢蘑菇中蘑菇氨酸含量的比较研究

蘑菇氨酸曾被怀疑具有潜在的致癌效应,但其生理作用目前还存在争议.为比较分析我国不同地区双孢蘑菇中蘑菇氨酸含量,本研究采用反相高效液相色谱法检测了我国5个双孢蘑菇产区30份新鲜双孢蘑菇样品中蘑菇氨酸的含量.结果显示,我国双孢蘑菇中蘑菇氨酸含量范围较广,为155.6～934.4mg/kg FW.在此基础上,分析了菌株类型、培养料类型和采收季节等因素对蘑菇氨酸含量的影响.结果表明,不同菌株、不同栽培条件下生产的双孢蘑菇中蘑菇氨酸的含量差异明显.     

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

The 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.     

Production of a protease inhibitor from edible mushroom Agaricus bisporus and its statistical optimization by response surface methodology

The production of a protease inhibitor from Agaricus bisporus through solid-state fermentation was studied. The purpose was to produce protease inhibitor from natural, cheap, and readily available carbon and nitrogen sources. Solid-state fermentation enhanced the mycelia growth and also gave a higher yield of the product. Further, fungal growth and other production parameters were statistically optimized. The specificity of the inhibitor was tested and was effective against trypsin. Screening of significant factors (wheat bran, cyanobacterial biomass, initial pH, temperature, incubation period, and moisture content and inoculum size) was performed using Plackett–Burman design. Central composite design was used to determine the optimized values of the significant variables which were found to be temperature (27.5°C), incubation time (156?hr), cyanobacterial biomass (1?g), and moisture content (50%) and gave a statistical yield of 980 PIU/g which was 25.6% higher than experimental yield (780 PIU/g). The inhibitor was purified by ammonium sulfate precipitation and diethylaminoethyl (DEAE) cellulose chromatography (yield 43.89% and 0.21%, respectively) and subjected to reversed-phase HPLC to validate its identity. Since protease inhibitors act against proteases, finding ample therapeutic roles; the isolated protease inhibitor from A. bisporus can also be a probable medicinal agent after its further characterization.     

Primordia initiation of mushroom (Agaricus bisporus) strains on axenic casing materials

The mushroom (Agaricus bisporus) has a requirement for a "casing layer" that has specific physical, chemical and microbiological properties which stimulate and promote the initiation of primordia. Some of these primordia then may develop further into sporophores, involving differentiation of tissue. Wild and commercial strains of A. bisporus were cultured in axenic and nonaxenic microcosms, using a rye grain substrate covered by a range of organic and inorganic casing materials. In axenic culture, A. bisporus (commercial strain A15) was capable of producing primordia and mature sporophores on charcoal (wood and activated), anthracite coal, lignite and zeolite, but not on bark, coir, peat, rockwool, silica or vermiculite. Of six strains tested, only the developmental variant mutant, B430, produced rudimentary primordia on axenic peat-based casing material. However, none of these rudimentary primordia developed differentiated tissues or beyond 4 mm diameter, either on axenic casing material in the microcosms or in larger-scale culture. In larger-scale, nonaxenic culture, strain B430 produced severely malformed but mature sporophores in similar numbers to those of other strains. Typically, 3-6% of primordia developed into mature sporophores, but significant differences in this proportion, as well as in the numbers of primordia produced, were recorded between 12 A. bisporus strains.     

Incorporation of radioactive shikimic acid into N-(γ-Lglutamyl)-4-hydroxyaniline in Agaricus bisporus

Agaricus bisporus contains novel aromatic compounds. By incubation of the mushroom with [G-¹⁴ C] shikimic acid, the radioactivity was incorporated into tyrosine, phenylalanine and several unidentified metabolites. The most radioactive metabolite in the stipe and the cap was identified as $\text{N-(γ-}\text{L}\text{-glutamyl}\text{)-4-}\text{hyrroxyaniline}$. The radioactivity was proved to be localized in the 4-hydroxyaniline moiety of this compound.     

原生质体紫外诱变选育姬松茸新菌株

对姬松茸原生质体进行紫外诱变处理,选育出在液体培养条件下生物量明显高于原始菌株的诱变株。经10代传代培养及摇瓶培养,表明该菌株稳定性良好,与出发菌株相比生物量提高5.5%,胞外多糖产量提高6.1%。     

Relative contribution of nematodes (Caenorhabditis elegans) and bacteria towards the disruption of flushing patterns and losses in yield and quality of mushrooms (Agaricus bisporus)

Laboratory tests of bacteria isolated from the body surface, or from the gut, of a saprophagous rhabditid nematode Caenorhabditis elegans infesting mushrooms (Agaricus bisporus) showed that some bacteria enhanced nematode reproduction and that others inhibited it. As some bacteria were shown to inhibit mycelial growth of the mushroom, the effects of Acinetobacter calcoaceticus var. anitratus, Enterobacter cloacae and Serratia liquefaciens, either alone or in combination with C. elegans, on the flushing patterns, quality and yield of A. bisporus (strain Horst U3) were studied. Bacteria alone had little effect on flushing patterns whereas C. elegans delayed the onset of mushroom production and significantly disrupted the growth pattern of crops, with mushrooms appearing more regularly and not within obvious flushes. Inoculation with bacteria resulted in ‘browning’ of mushrooms that was even more pronounced in C. elegans treatments. Characteristic distortion of sporophores was observed only in the presence of C. elegans. Nematodes commonly colonised sporophores. Bacteria affected the size of nematode populations both on the sporophores and in the casing. Significant yield loss occurred; up to 10% when bacteria were inoculated, up to 27.8% when C. elegans was inoculated, and up to 35% with both bacteria and nematodes. Synergism between C. elegans and A. calcoaceticus var. anitratus was observed; the combination resulted in significantly greater reduction in mushroom yield than any other treatment. It is concluded that bacteria contribute to yield loss and quality deterioration in A. bisporus but that the effects are far greater in the presence of C. elegans.