Mojgan Parvandi; Mohammad Farsi; Mohsen Ashrafi
Abstract
Introduction: The white button mushroom does not produce remarkable yield in the third flash. Nutritional deficiency and the inability of this mushroom to efficient use of compost are mentioned as its reasons. Basically, compost includes two major food components, lignocellulose and microbial biomass. ...
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Introduction: The white button mushroom does not produce remarkable yield in the third flash. Nutritional deficiency and the inability of this mushroom to efficient use of compost are mentioned as its reasons. Basically, compost includes two major food components, lignocellulose and microbial biomass. But this microbial biomass provides just 10% of button mushroom food needs. According to research studies, differentenzymes in both white button mushroom and oyster mushroom are responsible for decomposition of lignin compounds in compost media, from begin of mycelium grows to the end of fruiting. Lacasse, manganese peroxidase, lignin peroxidase, glyoxal oxidase enzymes contribute to degradation of lignin compounds in degradation mushroom has proven by researchers however itis dependent on mushroom types. Manganese peroxidase enzyme (EC. 1.11.1.13) is an extracellular parser lignin enzyme that has a central peroxidase core. Manganese peroxidase enzyme oxidizesMn2+ to Mn3+ and then Mn3+ oxidizes phenolic structure to fonoxile radical. Produced Mn3+ is very active and makes complex by chelating organic acids that is produced by mushrooms such as oxalate or malate. Mn3+ ions become stable by helping of these chelates and it can penetrate through materials such as wood. On the other hand, in recent years, plant biotechnology provides new solutions for old problems such as use of microorganisms, particularly using bacteria for gene transfer and improvement of superlatives. For a sample of this method, Agrobacterium-mediated transformation system can be noted. In addition, the use of suitable promoters for heterologous genes expression in suitable hosts is an important strategy in functional biotechnology that has been raised in edible mushroom genetic engineering. The lack of efficient and sufficient use of compost, low power of white button mushroom in competition with other rivals, lack of yield per area unit due to production costs, pests and diseases, low flexibility and adaptability with environmental conditions changes are some of the problems that the mushroom reformers are faced. Unlike the great efforts made by researchers, conventional breeding techniques to produce the A. bisporus mushroom only have been led to produce a few new races. Therefore, todays some problems associated with traditional methods of breeding of edible mushrooms, including the need to provide races that have desired characteristics, the traditional method performance tests and low chances of success in the transfer of important agronomic characteristics such as functionality and disease resistance. So, they almost have been replaced with new biotechnology methods. Anexample of this method is to manipulateproperties transformation for the particular purpose. Modification of both expression or type of lignin degrading enzyme are possible solutions to deal with this problem, but these are not applicable or are difficult to be done with traditional breeding programs. In recent years, gene transformation mediated with Agrobacterium routinely is used for gene transformation to mushrooms and is proposed as a method for removing limitations of white button mushroom breeding.
Materials and Methods: In this research, the oyster mushroom strain Florida was used as the source of manganese peroxidase (mnp) gene and white button mushroom strain 737 gill and cap tissue were used as transformation host. Agrobacterium strain LBA4404 harbors p133H88-FM plasmid thatcontainsmnp gene of oyster mushroom and also hph gene under control of gpdII promoter of the button white mushroom strain IM008 was used as a transformer. Selection medium containing 30 mg/ml Hygromycin B and was used for selecting transformed explants. To confirm transformation, PCR with specific primers of mnp and hph genes was performed on genomic DNA of selected colonies.
Results and Discussion: Results showed the gill tissue explants, with transformation rate 5%, have a better response to applied transformation method than cap tissue explants, with transformation rate zero percent. As expected, polymerase chain reaction with specific primers ofhph and mnp genes amplified 1049 and 1086 bp fragments and verified the transformation of mycelium's grown on selection medium. It seems that Bacterial strain and also used plasmid were one of the responses for observed low rate transformation which is in accordance with leach and co-workers study. Finally, we could propose that cap tissue is more suitable for further gene transformation of this mushroombecause of high transformation rate of cap tissue.
Saeid Nadi; Mohammad Farsi; Seyyed Hossein Nemati; Hossein Arouiee; Gholamhossein Davarnejad
Abstract
In this study, the recovery of casing soil consumed in the white button mushroom was investigated. Casing soil is used as a layer on compost (culture medium) to a diameter of 3-5to stimulate fruiting on the white button mushroom(Agaricus bisporus) . The expense od casing soil is about 30 percent of production ...
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In this study, the recovery of casing soil consumed in the white button mushroom was investigated. Casing soil is used as a layer on compost (culture medium) to a diameter of 3-5to stimulate fruiting on the white button mushroom(Agaricus bisporus) . The expense od casing soil is about 30 percent of production costs. In the first step of this experiment, in order to separate casing soil from compost easily (at the end of production period),by distribution of a mesh with pores of 5 mm between compost and casing soil in the casing step, which we could separate and easily collect casing soil at the end. The most important altering factor between chemical and physical properties of recycling casing soil, is EC that was reduced by leaching process. An experiment was conducted based on split plot design with two factors and three replications. The main plots were treated with two levels of with and without a plastic mesh. Percentages of recycled soils in combination with fresh casing soil applied in sub plots. Subplot included 100%, 75%, 50%, 25% and 0% of recycled soil. Three traits included fruit yield, fruit average weight and fruit number were analyzed using SAS software. None of the traits showed significant differences. No significant difference was obsereved between with and without plastic mesh. Further more no difference was observed between different percentages of recycled soil mixed with fresh peat. It is thus concluded that using recycled casing soil in production of the white button mushroom is possible and profitable.
Shirin Rezaei; Amir Lakzian; Mohammad Farsi; Mahboobeh Abolhassani-Zeraatkar; Gholamhossein Haghjnia
Abstract
One of the most important steps of Agaricus bisporus production is casing. In this step a layer of soil is added on top of compost. Peat is the most suitable casing soil for A. bisporus production. The lack of peat in Iran is one of the major problems in A. bisporus production for mushroom producers. ...
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One of the most important steps of Agaricus bisporus production is casing. In this step a layer of soil is added on top of compost. Peat is the most suitable casing soil for A. bisporus production. The lack of peat in Iran is one of the major problems in A. bisporus production for mushroom producers. It seems that peat can be replaced by Spent Mushroom Compost (SMC). In order to study the possibility of peat replacement, a factorial experiment was conducted in a completely randomized design layout with two replications. The experimental factors consisted of Spent Mushroom Compost with two levels (one and two years old), leaching with three levels (one (L1), two (L2) and three (L3) times) and EDTA with two levels (without EDTA (E1) and with EDTA, 0.3 M (E2)) and different casing soil with four levels (SMC+loam, SMC+Azolla, SMC+Peat (1:1) and Peat). The experiment was carried out in the Mushroom Production Center of Agricultural College, Ferdowsi University of Mashhad. The results showed that the highest mushroom yield was obtained in peat treatment (24%). The average of yield in SMC+Peat treatment was 11.78%. The Diameter of mushroom cap in SMC+Peat treatment was 44.1 mm. The lowest yield (8.1%) and diameter of A. bisporus cap (37 mm) was observed in SMC+Azolla treatment. The results also showed that the EDTA had a negative effect on yield (44.3 %) and diameter of the mushroom cap.