الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 102 |  |  |
| | | from | 102 | | |
Abstract
The mushroom cultivation is a profitable agribusiness. The technology of artificial cultivation of mushroom is somewhat recent innovation; incorporation of non conventional crops in existing agricultural system can help in improving the economic status of small farmers. Mushrooms are the good source of protein, vitamins and minerals. Mushrooms are the good source of extra ordinary power and virility and are used in the preparation of many continental dishes and have medicinal properties like anticancerous, anticholestrol, antitumorous. Mushrooms are useful against diabetes, ulcer and lungs diseases.The literature data concerning the cultivation technology of oyster in Egypt are scarce. The magnitude of effects of factors governing mushroom productivity and chemical structure of spent wastes after mushroom cultivation are only poorly understood. The present work was limited with respect to achieve the broad objectives of : Furthering the knowledge of oyster growth on different agricultural wastes. Gaining information concerning some factors influencing fungal yield. Studying chemical composition and cell wall decomposition for wastes used in oyster cultivation. The results obtained are summarized in the followings: 1. Comparison Pleurotus ostreatus strains growth and their decomposition for sterile rice straw: In this part of study, five strains of oyster mushroom, Pleurotus ostreatus (Jacq. ex. fr) Kummer, differing in mycelium extension rate and colony morphology were cultivated on synthetic medium and sterile rice straw. Under these conditions, growth rate and loss of organic mass were investigated. The obtained results are summarized in the followings: 1.1. Growth of fungal strains on artificial medium: Pleurotus ostreatus strains grown on artificial solid medium differed in their growth rates. Mycelium growth rate ranged from 4.47 to 10.10 mm/day. Pleurotus ostreatus PO 3 recorded the highest growth rate among the five tested strains. 1.2. Growth of fungal strains on natural substrate: The results indicate a positive correlation between the tested growth rate on GC 3% agar medium and on the natural substrate, i.e., rice straw.A higher growth rate on the agar plates corresponded to a higher ability to colonize sterile rice straw.1.3. Decomposition of fungal strains for sterile rice straw: The majority of P. ostreatus strains caused a higher loss of organic mass during cultivation at 25C for 60 days.The degradation of rice straw reached 32.20% within 60 days from P. ostreatus PO 3 inoculation. . Growth of Pleurotus ostreatus PO 3 on different agricultural wastes: In this part of thesis, the strain Pleurotus ostreatus PO 3 was chosen for cultivation on eight different organic wastes. The three important stages of fungal growth, namely spwan growth (25ºC), pin heads formation and fruiting bodies formation (20ºC) were followed.The obtained results revealed the followings: 2.1. The density of surface mycelium:The mycelium density was uniform, white, very thick and dense in the wheat straw, rice straw, barley straw, corn stalks, banana leaves and water hyacinth. The density of the mycelium was comparatively poor on sawdust and sugar cane bagasse. . Total colonization period of mycelium: The mycelium of the fungus totally colonised the sawdust within a period of 16.22-25 days of spawn run. The mycelium of the fungus totally colonised the sawdust within a period of 25 days of spawn run. 2.3. Diameter of mycelium growth: Generally, the diameter of radial growth of the mycelium was ranged from 4-5 cm / week during growth on various wastes. The highest mean radial growth of the mycelium was recorded on rice straw, followed by barley straw and wheat straw. 2.4. Premordia formation: The primordia appearing varied from substrate to another. The primordia started appearing 4–6 days after the bags had been transferred to the cropping room and opened Wheat straw used in mushroom cultivation gave the fastest mycelial growth rate. 2.5. Fruiting bodies formation: The fruiting bodies appeared 3-4 days after primordia formation. The fruiting bodies took 25.25-35.21 days later after inoculation of various organic wastes with spawn.2.6. Number average of fruiting bodies:Number average of fruiting bodies ranged from 16.70-25.23 / kg dry weight of organic matter. Rice straw waste recorded the highest number average of fruiting bodies (25.23 / kg dry weight of rice straw). Saw dust yielded the lowest number average of fruiting bodies (16.70 / kg dry weight of saw dust). 2.7. Mushroom yield: Very significant differences in mushroom yield were recorded during cultivation on various organic wastes. The highest oyster yield was harvested from rice straw yield (651.17 g/kg dry weight of rice straw). Biological efficiency: The biological efficiency for oyster grown on agricultural wastes tested varied greatly. The best biological efficiency, .i.e., 65.15%, was recorded in the case of rice straw waste, followed by wheat straw (62.53%). 2.9. Correlation of mushroom yield and waste components: Chemical composition of the by-products tested for P. ostreatus differed significantly in their components ratios. Significant (P<0.05) positive relationship recorded between waste content and Oyster yield. 3. Effect of reduction of rice straw size and particles size: Generally grinding method yielded better results concerning oyster yield, biological efficiency and substrate dry matter loss than chopping method. This may be due to grinding as mechanical method ruptured the cell walls of the rice straw to a greater degree, potentially making the nutrients in the rice straw more accessible for P. ostreatus growth. The P. ostreatus mushroom also grew faster on the ground straw, than on the chopped straw, with their growth cycles being shorter than on the chopped straw. No significant difference was found between the two sizes, 2.5 and 5.0 cm, of the chopped straw. Further reduction of the particle size by grinding the straw to 0.5 cm, however, resulted in lower mushroom yield. This could be because the particles that were to small resulted in the over-compaction of rice straw in the cultivation bags, which may have led to hindered air exchange between the void spaces in the substrate and headspace, especially when the bags were closed. 4. Effect of spawn inoculation level: With the tested spawn levels, 6% and 9% levels (on the basis of dry weight of organic matter) resulted in significantly lower mushroom yield than the other levels. Spawn level 12% (on the basis of dry weight of organic matter) enhanced mushroom yields. . Effect of inoculation with Pseudomonas fluorescence: Addition of P. fluorescence inoculum had beneficial impact for mushroom production and biological efficiency. P. fluorescence inoculum appreciably reduced total number of days for cultivation of about 2 days compared with uninoculated treatments. 6. Chemical composition and decomposition of waste cell walls: The crude protein content reached 6.14 g/100 g dry matter basis of spent rice straw. The fungal cultivation reduced (p<0.05) the cellulose content of the rice straw. Hemicellulose content in spent rice straw showed a similar trend. Organic matter content decreased from 80.15 to 64.20 g / 100 g dry matter basis.