Earticle

Spawn is the vegetative growth of the mycelium and serves as the inoculum or seed for cultivating mushrooms. Various cereal grains, such as wheat, millet, barley, sorghum, brown rice, rye, and oat were assessed to compare their characteristics and suitability for spawn production of button mushroom (Agaricus bisporus). The mycelial growth rates, density, and the number of completely colonized grains were measured from the twentieth day of inoculation. Wheat grains showed fastest mycelial growth with 8.4 cm followed by rye, oat, barley with 8.2, 7.5 and 7.3 cm, respectively. In the mycelial density, foxtail millet, barley, and sorghum were best compared with that of wheat grains. Especially, the number of grains which were completely colonized by mycelia were greatest in foxtail millet with 5,123 grains followed by proso millet, and wheat with 3,052 and 914, respectively. Based on the results obtained, barley, foxtail millet, and sorghum grains would be appropriate substituting for wheat grain in spawn production of button mushroom.

This study was carried out to investigate the management characteristics and growth performance of L. edodes from the cooling stage to incubation. Bags of different heights and weights are available for bagging. When the medium size of 17x13 cm was used and the size of the inoculation hole was changed from 1/3 to 2/3, the browning period was shortened to 30 days. Mycelial growth was evaluated according to the cooling temperature after sterilization. It was observed to be the highest at 122 mm/15 days at 10oC and 114 mm/15 days and 117 mm/15 days at 15oC and 20oC, respectively. The contamination rate of the sawdust media before inoculation was measured as 0, 4.5x10, 1.3x102, 4.0x103 cfu at 5oC, 10oC, 15oC, and 24oC respectively. The average of 1.6x108 colony forming units (cfu) of microorganisms was observed in the sawdust that had been piled for six months outdoors. In summer, the sawdust has to be used immediately after mixing. The sterilized medium had an average of 4x103 cfu of microorganisms at 24oC and 1.3×102 cfu at 15 °C. After 15 days of inoculation in vitro, the growth conditions of the sawdust was the best at 132 mm, followed by grain and liquid. When inoculated with liquid spawn, the moisture content of the substrate should be adjusted between 50% and 55% in advance.

This study was conducted to establish an appropriate period of use of sawdust spawn at low temperatures and a nutrient supplement medium for cultivation of Lentinula edodes ‘Hwadam’. Of the nutrient supplements, the total yield of rice bran (5%) + corn flour (5%) treatments were 673.3 g, which was higher than rice bran (551.6 g) and wheat bran (546.7 g) treatments, respectively. As shown by the growth of Lentinula edodes ‘hwadam' during to the sawdust spawn storage period (at 4oC), the period of spawn running, browning, fruiting body formation, and development was 27 d, 81 d, 5 d, and 11-13 d, respectively, regardless of the length of the storage period at 4 oC. After 3 months of storage of sawdust spawn, the number of fruiting bodies and yield decreased as the storage period increased. Therefore, the period of use of sawdust spawn (at 4 oC) for the stable production of fruiting bodies of Lentinula edodes ‘Hwadam’ was a maximum of 3 months.

Currently, the spawn of the mushroom Agarcus bisporus is produced by a method developed in the 1980s, and anew spawning method needs to be developed to improve the quality of the spawn. In this study, the condition for a maximum mycelium weight(5.92±0.52 g/L) was shaking culture (24 hours/day) at 24°C and 120 rpm in CDB (compost dextrose broth). Based on this, the ventilated liquid culture method (2.5 L/min) was cultured for 10 days. This method was appropriate, andwhen the inoculum was cultured at 50 g/mL for about 10 days, it was cultured well without agglomeration and shaking of seed.

This study was aimed to improve the productivity and income of mushroom farming by developing a new casing material as a substitute for clay loam casing soil, which is becoming more difficult to acquire. When the new casing materials were used for the stable production of button mushroom (Agaricus bisporus), a 1:1 mixture of clay loam and button mushroom media obtained after harvest supported 13% greater mycelial growth (32.0 kg/3.3 m2). This material was better than clay loam soil in preventing contamination with environmental compounds and pests. The use of an inexpensive 1:1 mixture of peat moss and coco peat resulted superior mycelial growth with 4% better yield (32.9 kg/3.3 m2) compared with conventional clay loam soil. Advantages of these casing materials included ready availability and improved productivity. Mixtures of peat moss + coco peat + zeolite (50%:30%:20%) and coco peat + coal ash (75%:25%) could substitute for conventional casing soil. Additionally, the novel mixtures containing material obtained after cultivation might be used to produce organic fertilizer.

To develop Grifola frondosa as a new commercial product, we investigated the optimal primordium formation method for bottle cultivation. Primordium formation was initiated on the sixth day in all treatments, but in the T7 treatment, which consisted of removing old spawn and turning the bottle upside-down, was initiated on the ninth day. The ratio of primordium formation was at its highest value, 98.9%, in T3 and T7. Among the treatments, T7 produced the highest quality fruiting bodies and a mushroom yield of 112.8 g in each 850 mL bottle, but its crop cycle time was somewhat longer than those of the other treatments. These results indicate that appropriate methods for primordium formation in bottle culture could enhance mushroom quality and productivity.

The word spawn is derived from an old French verb, espandre , meaning to spread out or expand. Spawn is also defined as “the mycelium of fungi, especially of mushrooms grown to be eaten, used for propagation.” The effects of bag spawn to sawdust substrate on the growth of Pleurotus ostreatus were conducted. The duration of mycelial growth and days of pinhead formation of bag spawn(2.5kg) were 18~19 days and 7~8 days, whereas bottle spawn (1,000㎖) was 18 days and 6 days, respectively. The yield of mushroom fruitbody was that bag spawn is 100~118g, bottle spawn was 95~115g. In economical analysis, bag spawn is increased to 50%, compared to bottle spawn in relative income.

The button mushroom, Agaricus bisporus, was one of the most widely cultivated mushroom. The domestic production of cultivated mushroom was almost 10,638 tons with a total value of 59 billion won in 2017. Currently, 10 Korean cultivars have been developed, but farmers don’t use them because spawn quality. Korean spawn is inoculated with grain mother spawn and incubated in glass bottle. This experiment was conducted to improve the current spawn manufacturing system. The Compost Dextrose Broth (CDB) was selected many kinds of media for liquid culture. The 80 plugs of mycelium were inoculated in 800 ml CDB and mycelia were cultured in 120 rpm shaking incubation. The mycelium was well cultured by putting at least 4 ml of liquid inoculum in 45 g of grain medium. Based on this, 1.5 plates of mycelium was inoculated in 3 L CDB using liquid incubator in which normal air was injected, and the culture was completed in about 14 days. These results will be supplemented by application to Korean spawn companies.

The button mushroom, Agaricus bisporus is one of the most widely cultivated mushroom species. Mushroom growers inoculate compost beds with spawn, which is the vegetative mycelium and serves as the inoculum or seed for cultivating mushrooms. Various cereal grains, such as wheat, millet, barley, sorghum, brown rice, rye, and oat can be used in the spawn production of button mushroom. In this study rice seed bag spawn was compared with wheat grain bottle spawn in the spawn production. When the physical properties of two cereal grains were compared the 1000-kernel weight were 32.0g in wheat grain and 24.9g in rice seed. Number of kernels per milliliter were greater in rice seed compared with wheat grain with 24.5. Wheat grain showed 41.0% of total carbon level and 2.49% of total nitrogen level resulting 16.6 C/N ratio. Nitrogen content of rice seed was lower compared to that of wheat with 0.96 resulting 39.5 C/N. It was possible to produce 50kg of rice seed spawn in 22×49cm polypropylene filter bag with only 1~2 shakings compared to 0.45kg of wheat grain spawn in 1,000mL Ringer bottle with 4~5 shakings. Based on the results obtained, rice seed bag spawn would be appropriate substitute for wheat grain spawn in button mushroom.

To minimize cultivation costs, prevent insect-pest infestation, and improve the production efficiency of thermophilic mushrooms, plant substrates obtainedfrom local areas in Cambodia were used for production of both spawn and mushrooms. In this experiment, different sawdusts different organic wastes and grain ingredients and analyzed for improvement of spawnproduction efficiency. Four thermophilic mushroom species, Pleurotus sajor-caju (oyster mushroom, Sambok), Ganoderma lucidum (deer horn shaped), Auricularia auricula (ear mushroom), and Lentinula edodes (shiitake), were used to identify efficient new substrates for spawn and mushroom production. Although the mycelia in the rubber tree sawdust medium showed a slightly slower growth rate (10.9 cm/15 days) than mycelia grown in grains (11.2 cm/15 days in rice seeds), rubber tree sawdust appeared to be an adequate replacement for grain spawn substrates. Th findings indicate that rubber tree sawdust, sugarcane bagasse, and acaciatree sawdust supplemented with rice bran and calcium carbonate could be new alternative the substrates for . Although sugarcane bagasse and rubber tree sawdust showed similarly high biological efficiencies (BE) of 60% and 60.8%, respectively, acacia tree sawdust exhibited relatively a low biological efficiency of 22.4%. However, it is expected that acacia sawdust has potential for the mushroom cultivation when supplemented with currently used sawdust substrates in Cambodia, because of its relatively low price. The price of the sawdust (20 kg sawdust= 6500 Riel or 1.6 USD) currently used was 6.5 times higher than the price of acacia sawdust (201000 Riel or 0.25 )USD). Therefore, utilization for acacia sawdust for mushroom cultivation could become feasible as it would reduce by producing costs of mushrooms in rural areas of Cambodia.

In this study we attempted to analyze the change of protein and mycelial activity during low temperature storage progressed. At first, esterase and peroxidase isozymes were detected at third and fourth subculture in Pleurotus ostreatus and peroxidase isozymes in Pleurotus eryngii were detected at first and second subculture but esterase isozymes showed almost same band patterns subculture advanced. The decolorization ratio of media color including indicator were decreased according to subculture advanced in P. ostreatus and P. eryngii. However there were not significantly difference of mycelial growth, fruit body yield, esterase isozyme band pattern and laccase activity of P. eryngii according to storage periods at low temperature. Therefore, it was possible to store sawdust spawn of P. eryngii at 4℃ for 120days.

In this study we attempted to analyze the change of protein and mycelial activity during low temperature storage progressed. At first, esterase and peroxidase isozymes were detected at third and fourth subculture in Pleurotus ostreatus and peroxidase isozymes in Pleurotus eryngii were detected at first and second subculture but esterase isozymes showed almost same band patterns subculture advanced. The decolorization ratio of media color including indicator were decreased according to subculture advanced in P. ostreatus and P. eryngii. However there were not significantly difference of mycelial growth, fruit body yield, esterase isozyme band pattern and laccase activity of P. eryngii according to storage periods at low temperature. Therefore, it was possible to store sawdust spawn of P. eryngii at 4℃ for 120days.

Spawn is pure culture of vegetative mycelium and has an important to play as the inoculum or seed in cultivating mushrooms. Different grains are used as spawn in button mushroom Agaricus bisporus. Various cereal grains, such as wheat, millet, barley, sorghum, brown rice, rye, oat were assessed to compare their suitability for production of button mushroom spawn. The mycelial growth rates, density, and the number of completed grains were measured from the twentieth day of inoculation. Wheat grains showed fastest mycelial growth with 8.4 cm followed by rye, oat, barley with 8.2, 7.5 and 7.3 cm, respectively. However, they were not significantly different at the 0.05 level. In the mycelial density, foxtail millet, barley, and sorghum were best compared with that of wheat grains. Especially, the number of grains which were completely colonized by mycelia were greatest in foxtail millet with 5,123 grains followed by proso millet, and wheat with 3,052 and 914, respectively. Based on the results obtained, barley, foxtail millet, and sorghum grains would be most appropriate for grain spawn production substituting wheat grain in button mushroom.

The word spawn is derived from an old French verb, espandre, meaning to spread out or expand. Spawn is also defined as “the mycelium of fungi, especially of mushrooms grown to be eaten, used for propagation.” The effects of bag spawn to sawdust substrate on the growth of Pleurotus ostreatus were conducted. The duration of mycelial growth and days of pinhead formation of bag spawn(2.5kg) were 18~19days and 7~8days, whereas bottle spawn (1,000㎖) was 18days and 6days, respectively. The yield of mushroom fruitbody was that bag spawn is 100~118g, bottle spawn is 95~115g. In economical analysis, bag spawn is increased to 50%, compared to bottle spawn in relative income.

To improve the productivity of Pleurotus ostreatus, different conditions of liquid spawn culture were tested. The optimum culture conditions were potato dextrose broth, incubation temperature of 22oC, and pH 6. Fifteen different media (‘A’ to ‘O’) containing 0.3% soybean meal (SM) were prepared by varying sugar and glucose contents. The cultures were propagated in SM media for 14 days, at 22oC, and pH 6. Their absorbances were higher after 14 days of incubation in the media containing both sugar and glucose. In particular, the absorbance of media containing 5 to 20% of glucose alone (‘C’, ‘D’, ‘E’, and ‘F’) tended to increase in the incubation period. Dry cell weight was lower in media containing less than 20% sugar or glucose alone than in media containing 30% sugar (‘A’) or 30% glucose (‘B’) alone. In sawdust media, in 900 mLbottle, the optimum inoculation volume of liquid spawn was 15 to 20 mL. The texture of the mushroom cultivated with the liquid spawn was superior to that cultivated in the solid spawn.

Studies were processed to confirm the difference of the shiitake productivity according to different spawn shapes(sawdust, plug-shaped and liquid spawns) on middle-temperature type strain. A tendency of fruiting was similar among three treatments, and treatments inoculated with plug-shaped spawn and liquid spawn produced over 50 % of total yield until 2nd flushing period and 80 % of total yield until 4th flushing period. In investigation of deformed fruitbodies, all of three treatments occurred until 2nd flushing period. However, in rate of deformed fruit-bodies, treatment inoculated with liquid spawn was lower than others. In investigation of yield, the amount produced on treatment inoculated with liquid spawn was 411 g per medium and it was highest among treatments. And the amount of fruit-bodies over 10 g was higher than others. Also, the number of fruit-bodies between sawdust and plug-shaped spawn was different, but each weight of fruit-bodies among three treatments was not different.