계종버섯은 중국에서 맛과 향에서 최고의 버섯으로 평가받고 있으며, 본초강목에 그 효능이 기록되어 전해지고 있으나 효능과 물질연구 및 인공재배법 개발이 요구되고 있는 상황이다. 항산화 활성과 항염증 활성을 가지는 기능성 물질의 확보와 기능성식품 개발을 위한 기초자료를 확보하기 위하여 유기용매 추출물과 열수 추출물을 제조 하고, 활성이 높은 분획물을 얻고자 하였다. CH2Cl2와 MeOH 혼합용매로 추출한 다음 비극성용매와 극성용매로서 용해성에 따라 분획하고, 열수 추출로 추출물을 확보하였다. 분획물과 추출물을 이용한 항산화 활성 조사에서 는 열수 추출물(TA4)의 DPPH 라디칼 소거능에 대한 IC50값이 1.5 mg/mL로 나타났고, MeOH 분획물(TA2)에서는 IC50값이 1.93 mg/mL로 높게 나타났다. NO생성 억제율로 조사한 항염증 활성은 EtOAc 분획물(TA1)은 조추출물이지만 100 μg/mL 처리농도에서는 79% NO생성이 억제되고, 200 μg/mL 농도에서는 NO가 전혀 생성되지 않았다. TA1 물질을 2차례 TLC로 분리한 TA1-5-6물 질은 15 μg/mL 처리농도에서 대조구와 비교하여 NO생성이 86% 억제되었고, 30 μg/mL 농도에서는 NO 생성이 완전히 억제되었다. 그리고 세포독성 실험에서는 50 μg/mL 농도에서도 전혀 독성이 나타나지 않았다. MeOH 분획물 (TA2) 유래의 TA2-1-5물질은 30 μg/mL 처리농도에서 75% 이상 NO생성이 억제되었으며, 세포 독성은 50 μg/mL에서도 아주 낮게 나타났다. 선택적 용매의 선별과 추출 방법의 개발을 통하여 세포 독성이 없고, 생리활성이 뛰어난 계종버섯 분획물 확보가 가능하였고, 기능성식품 및 건강 기능성소재로서의 충분한 잠재력을 확인할 수 있었다.

국내에서 가장 많이 재배되고 있는 버섯은 느타리류로 일반느타리와 큰느타리(새송이) 두 품목이 대부분을 차지한다. 그 중에서 큰느타리는 자동화 시설이 확대되면서 생산량이 크게 증가하였으며, 저장성이 우수하여 수출되는 버섯의 주요 품목 중 하나로 자리잡았다. 그러나, 생산량이 점차 증가하면서 가격이 다소 하락하였고 이에 생산자는 큰느타리를 대체할 수 있는, 소비자는 버섯 시장의 선택의 폭을 넓힐 수 있는 새로운 버섯 품목 개발을 요구해 왔다. 이에 따라, 국립원예특작과학원에서는 중국 등 아시아 에서 맛과 향이 우수하여 고품질로 생산되고 있는 백령느 타리와 아위느타리를 종간교잡하여 ‘크리미’라는 품종을 개발하였다. 기존에 육성된 품종 및 수집된 유전자원을 재배하여 형태적 특성검정을 하였고, 아위느타리 품종 ‘비산2 호(KMCC00430)’ 와 백령느타리 유전자원 ‘KMCC00461’ 을 모본으로 선발한 뒤 각 모본으로부터 단포자를 분리하여 mono-mono 교잡하였다. 약 1,000 조합의 교잡을 하였 고, 그 중 73계통이 교잡이 확인되어 재배시험 및 자실체 특성조사를 수행하였다. 그 중 갓이 밝은 연백색이며 대가 굵고 곧아 품질이 우수한 ‘7773’ 계통을 최종선발하였고 ‘크리미’라고 명명하였다. ‘크리미’의 균사생장 적온은 25~30 ̊C이고, 자실체 생육온도는 16 ̊C이다. 농가에서 대량생산시험 후 현장평가회 및 시식회를 개최해 본 결과, ‘크리미’의 수량이 대조구 ‘백황’보다 약 5% 증수되었고, 기존 아위느타리 품종 ‘비산2호’에 비해 식감과 맛이 더 우수하며, 아위x백령느타리 품종 ‘백황’보다 자실체 형태 가 더 우수하여 고품질로 판매가 가능할 것이라는 평가를 얻었다. 큰느타리와 다르게 밝은 연백색인 갓을 가졌으며, 식감과 향이 더 우수한 아위x백령느타리 신품종 ‘크리미’가 앞으로 버섯 농가의 새로운 소득 창출과 버섯 시장의 품목 다변화에 이바지할 것을 기대해 본다.

In Korea, oyster mushroom is one of the commonly cultivated mushrooms. In 2013, the cultivation areas and products of oyster mushrooms were 60,039 M/T and 201 ha, respectively. Many species of oyster mushrooms are cultivated in various countries. These include Pleurotus ostreatus, P. florida, P. sajor-caju, P. eryngii, P. citrinopileatus, P. salmoneostramineus and P. cystidiosus. P. citrinopileatus is a yellow oyster mushroom famous for its health benefits such as anti-cancer and anti-oxidant effects. Therefore, a cultivar P. citrinopileatus ‘Jangdari’ was developed to improve yield and the ability to grow well at lower temperatures. Two parent strains ‘Gumbit (KMCC02150)’ and ‘KMCC02145’ were selected based on their morphological characteristics. ‘Jangdari’ was developed by the method of Mon-Mon crossing between monokaryons derived from ‘Gumbit’ and ‘KMCC02145’, and finally selected through continuous cultivation tests. The optimum temperature for mycelial growth was 30oC. The cultivar could grow well at high temperatures, especially 16~24oC. Fruiting body production per bottle (850 mL) was about 90.0 g. Stipe length and thickness of ‘Jangdari’ were similar to those of ‘Gumbit’. ‘Jangdari’ was more resistant to low temperature than ‘Gumbit’, and thus it could be cultivated with oyster mushrooms (P. ostreatus). In addition, while cultivating ‘Jangdari’, it is not required to scrape out the upper side of bottle’s sawdust medium; hence, its cultivation is expected to save energy and time.

Microsatellite SSR markers were developed and utilized to reveal the genetic diversity of 32 strains of Flammulina velutipes collected in Korea, China, and Japan. From SSR-enriched library, 490 white colonies were randomly selected and sequenced. In the 490 sequenced clones, 85 clones (17.35%) were redundant. Among the remaining 405 unique clones, 201 clones (49.6%) contained microsatellite sequences. As a result, 12 primer pairs produced reproducible polymorphic bands within diverse 4 strains and these selected markers were further characterized in 32 Flammulina velutipes strains. A total of 34 alleles were detected using the 12 markers, with an average of 3.42 alleles and the number of alleles ranged from two to seven per locus. The major allele frequency ranged from 0.42 (GB-FV-127) to 0.98 (GB-FV-166), and values for observed (HO) and expected (HE) heterozygosity ranged from 0.00 to 0.94 (mean = 0.18) and from 0.03 to 0.67 (mean = 0.32), respectively. SSR loci amplified with GB-FV-127 markers gave the highest polymorphism information content (PIC) of 0.61 and mean allele number of five, while for loci amplified with GB-FV-166 markers these values were the lowest, namely 0.03 and two. The mean PIC value (0.29) observed in the present study with average number of alleles (3.42). The genetic relationships among 32 Flammulina velutipes strains based on SSR data were generated by UPGMA cluster analysis. In conclusion, we succeeded in developing 12 polymorphic SSRs markers from SSR-enriched library of Flammulina velutipes. These SSRs are presently being used for phylogenic analysis and evaluation of genetic variations. In future, these SSR markers will be used in clarifying taxonomic relationships among the Flammulina velutipes.

‘Baekseung’, a new variety of Flammulina velutipes, was bred by mating two monokaryotic strains isolated from KMCC 4210 and KMCC 4216 in Mushroom Research Division, Baekseung ARES in 2016. Baekseung showed fast mycelial growth and high mycelial density on MEA (Malt Extract Agar) media for 7days of incubation. Spawn running period on the sawdust substrate required 30days at 25°C. The cultivation period and optimum temperature were 11±1 days at 14°C for primordia formation and 14±1 days at 7°C for fruiting body development. The length of pilei and stipes in Baekseung harvested in optimal stage exhibited 11.3±0.4㎜ and 89.2±7.1㎜ and Megumi harvested in optimal stage showed 8.2±1.0㎜ and 95.9±5.0㎜ respectively. Yield of Baekseung and Megumi strain grown of sawdust substrate was 153.7±12.5g and 150.5±29.7g per 850ml in bottle cultivation. The inferred tree exhibited the difference of phylogenetic relationship between the Korean white fruiting body strains such as Baekseung, Uri1ho, Fv-14-a-38, and Fv-14-a-51 and the Japanese white fruiting body strain Megumi.

In this study, we made population with high biological efficiency to investigate the complex genetic architecture of yield-related traits in A. bisporus. MB013 that crossed with bisp 15-p2 and bisp 34-p2 had high biological efficiency. 170 homokaryons was isolated with CAPS marker (PIN primer/HaeⅢ) from 1000 ISSs. And 100 BC1F1 hybrids obtained by crossing the homokaryons of MB013 with bisp15-p1. Parental line bisp 15-p2 and bisp 34-p2 and 100 homokaryons of MB013 will analyze genome sequencing. Also 100 BC1F1 hybrids will evaluate yield-related traits.

Chronic inflammation, which results from continuous exposure to antigens, is one of major reasons for tissue damage and diseases such as rheumatoid arthritis and type 2 diabetes. In this study, we investigated the anti-inflammatory effects of extracts (hexane, CHCl3, MeOH, MeOH/H2O, and H2O) from GW10-45, which is our new cultivar of an edible mushroom Pleurotus ferulae (ASI 2803 and ASI 2778), in RAW264.7 murine macrophages. None of the extracts showed cytotoxicity in RAW264.7 cells and the hexane, CHCl and H extracts reduced nitric oxide (NO) production, an important inflammatory marker, in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Particularly, the extract (CG45) inhibited NO production more than the other extracts did. To elucidate the effects of CG45 on molecular targets involved in proinflammatory responses, we performed western blot analysis. Expression of inducible nitric oxide (iNOS) significantly decreased in LPS and CG45 co-incubated cells compared to that in LPS only-treated cells. Additionally, another protein thatplays a critical role in inflammation, was down-regulated in cells treated with both LPS and CG45. In the nuclear factor (NF)- B pathway, phosphorylation of I Bα decreased in RAW264.7 cells treated with both LPS and CG45. Furthermore, CG45 inhibited the phosphorylation of NF- B in LPS-stimulated RAW264.7 cells. Conclusively, CG45 could suppress proinflammatory responses in LPS-stimulated RAW264.7 cells by down-regulating not only the phosphorylation of NF- B and I Bα but also the expression of iNOS and COX-2 without any cytotoxicity.

Oyster mushrooms are widely cultivated and consumed in Korea. P. ostreatus 'Suhan(ASI 2504)' is an ideal cultivar for mushroom farmers due to its dark pileus and thick stipe; however, as it is very sensitive to environmental conditions, an alternative cultivar is required. To develop a new cultivar, parental strains 'Suhan(ASI 2504)' and ‘ASI 0665 (Heuktari)’ were selected from various collected strains according to morphological characteristics. P. ostreatus ‘Soltari’ was developed by Di- Mon crossing between the dikaryotic strain ‘Suhan’ and the monokaryotic strain derived from ‘Heuktari’. Thirty-eight of the 100 crossed strains were selected following analysis of mitochondrial genetic characteristics, and 'Soltari' was ultimately selected by continuous cultivation tests. The mitochondrial DNA profile of ‘Soltari’ was found to be the same as that of ‘Heuktari, and a nuclear DNA profile of ‘Soltari’ was similar as those of the parental strains, ‘Suhan’ and ‘Heuktari.’ 'Soltari' mycelium grows adequately in moderate to high temperatures of 12–20oC, although its optimum temperature was found to be 30oC. Fruiting body production per 1.1-L cultivation bottle was approximately 158.8 g. Its stipe length and thickness were comparable to those of diameter and thickness were somewhat lower (42.72 vs. 51.33 mm and 18.18 vs. 22.46 mm, respectively). ‘Soltari’ was found to be more resistant to high CO2 atmosphere than 'Suhan', and the color of the pileus of 'Soltari' was dark gray at high temperature. Therefore, it is suggested that this new cultivar ‘Soltari’ is a good alternative cultivar and will contribute to energy saving in oyster mushroom farms.

The production scale of mushrooms in Korea is approximately 600 billion won, which is 1.6% of Korea’s gross agricultural output. In Korea, ca. 190,000 tons of mushrooms are harvested annually. Although the numbers of mushroom farms and cultivators are constantly decreasing, total mushroom yields are increasing owing to large-scale cultivation facilities and automation. The recent expansion of the well-being trend has caused an increase in mushroom consumption in Korea: the annual per capita mushroom was 3.9 kg (’13), whichis a little higher than that in Europe. Thus, mushroom export, mainly Flammulina velutipes and Pleurotus ostreatus, has increased since the mid-2000s. Recently, however, it is slightly reduced. Nevertheless, Vietnam, Hong Kong, the United States, and the Netherlands continue to export mushrooms, and Korea has increased its export to Australia, Canada, Southeast Asia, etc. Canned Agaricus bisporus, the first export of the Korean mushroom industry, reached it speak sales in 1977-1978. When Korea initiated trade with China in 1980, the international prices of mushrooms fell sharply, leading to shrinkage of the domestic markets. Spurred by the high demand to develop substitute goods for A. bisporus, the oyster mushroom (P. ostreatus) gained attention since it seemed to suit the taste of Korean consumers. Although the log cultivation technique for oyster mushroom was developed in the early 1970s, it required a great deal of labor. Thus, we developed the shelf cultivation technique, which is easier to manage and allows for mass production. In this technique, the growing shelf is made mafrom fermented rice straw, whichis the only P. ostreatus medium in the world and isused only in South Korea. After then, the use of cotton wastes as an additional material of medium, the productivity. Currently, we are developing a standard cultivation technique and environmental control system that can stably produce mushrooms throughout the year. The increase of oyster mushroom production may boostthe domestic market and contribute to industrial development. In addition, oyster mushroom production technology played a role in forming the basis for the development of bottle cultivation, which made mass production . In particular, bottle cultivation using liquid spawn could allow for the export of F. velutipes and Pleurotus eryngii. In addition, the white varieties of F. velutipes were second developed in the world after Japan. We also developed the new A. bisporus cultivar ‘Saeah’, which is easy to grow in Korea. In hopes to advance the mushroom industry, we will continue to develop cultivars with international competitive power and to improve cultivation techniques.

‘Mantari’ is a new variety of oyster mushroom for bottle culture. It was bred by crossingmonokaryons isolated from ‘DM11732’ and ‘Chunchu-2ho’. The optimum temperature for the mycelial growth was 26~29°C on PDA medium, and that for the primordia formation and the growth of fruiting body of ‘Mantari’ on sawdust mediawas 18°C and 16°C. It took 32 days to finish spawn running, 4 days to finish primordia formation, and 3 days to finish fruiting body growth in the bottle culture. The fruitcharacteristics: the pileus was round and gray-black in color, and the stipe was long, thin, and light gray in color. The yield per bottle was 179 g/900 ml and was 5% higher than that of the control variety (Chunchu-2ho). The physical properties of the fruit body were as follows: springiness, cohesive, gumminess, and brittleness of the stipe tissue were 96%, 76%, 160 g, and 15 kg, respectively.

Oyster mushroom is one of mushrooms that are cultivated and consumed a lot in Korea. P. ostreatus 'ASI 2504(Suhan)' is a preferable cultivar to mushroom farmers because it has a dark pileus and a thick stipe. But it is very sensitive to environmental conditions, so farmers demand an alternative cultivar of ‘Suhan’ continuously. To develop a new cultivar, parental strains ‘ASI 2504(Suhan)’ and ‘ASI 0665(Heuktari)’ were selected from P. ostreatus’s various collected strains according to morphological characteristics. P. ostreatus ‘Soltari’ was developed by the method of Di-Mono crossing between dikaryotic strain ‘Suhan’ and monokaryotic strain derived from ‘Heuktari’. Analysis of the mitochondrial genetic characteristics was performed for primary selection in 100 crossed strains. The mitochondrial DNA profile of ‘Soltari’ was same as that of ‘Heuktari’, when mitochondrial DNA primer MtPo1 was used. And a nuclear DNA profile of ‘Soltari’ was similar as those of the parental strains, ‘Suhan’ and ‘Heuktari’, when RAPD(Random Amplified Polymorphic DNA) primer URP 1, 3 were used. The optimum temperature for mycelial growth was 30°C for ‘Soltari’. ‘Soltari’ was appropriate for middle high temperature to grow, especially 13~18°C. Fruiting body production per bottle (1,100mL) was about 158.6g. When compared to the control strain ‘Suhan’, the stipe’s length and thickness of ‘Soltari’ were similar to those of ’Suhan’. But the pileus diameter of ‘Soltari’ was a little shorter than that of ‘Suhan’, the former was 42.72mm, while the latter was 51.33mm. And the pileus thickness of ‘Soltari’ and ‘Suhan’ were 18.18mm and 25.46mm, respectively. ‘Soltari’ was more resistant at high CO2 concentration than ‘Suhan’ and the color of pileus of ‘Soltari’ was kept dark gray at high temperature. Therefore, it is suggested that this new cultivar ‘Soltari’ be an alternative of ‘Suhan’ and contribute to energy saving effect in oyster mushroom farms.

느타리 버섯류의 새로운 품종을 개발하기 위해 고품질 의 흑회색 느타리 신품종을 육성하였다. 2003년부터 2004년까지 느타리 유전자원의 특성을 검정하였고, 2008 년에 수한과 농기201호의 단핵체간 교잡하여 04-154 교 잡주를 육성하여 이를 이용해 구슬, 만추리, 야산을 육성 하였다. 2012년 구슬의 이핵체와 야산의 단핵체를 교잡하 여 몽돌을 육성하였고, 이 몽돌과 곤지7호를 교잡하여 갓 색깔이 우수한 Po 2012-706를 선발하여 특성검정, 확대 재배를 실시하여 농작물 직무육성 신품종 선정심의회에서 ‘고솔’로 명명하였다. 주요특성으로 균사 생장 적온이 25~30 o C이며 버섯 원기형성 및 발생온도는 12~18 o C이다. 자실체의 갓 색깔은 흑회색이며 자실체 형태는 옅은 깔때 기형이다. 대길이는 42.4±2.7 mm, 대굵기는 14.6±2.7 mm 로 수한에 비해 자실체 대가 가늘면서 긴 편이다. 자실체 수량은 병 당(850 mL) 124.2±35.2 g으로 수한이 100일 때 고솔은 116이었다. 가변특성으로는 감자배지와 버섯완전배지에서 균사를 배양한 결과 버섯완전배지에서 생장이 양호하였고 대조구 또한 같은 결과를 보였다. 4종류의 primer를 이용하여 새로운 품종 ‘고솔’과 모균주에 대한 DNA profile을 분석한 결과 primer URP1, primer URP2 에서 고솔이 양친의 주요 DNA 밴드를 갖고 있으며 대조 구인 ‘수한’과는 뚜렷하게 구분되었다. 신품종 느타리 ‘고 솔’은 소비자들이 선호하는 흑회색의 갓을 나타났고 저장 성이 좋아 고품질을 요구하는 소비자들을 만족시키는 데 기여할 것으로 기대된다.

팽이버섯 내에 존재하는 GAD 효소를 발효를 통해 활 성화 시켜 MSG를 GABA로의 전환율을 높이고자 하였다. 효과적인 고농도 GABA를 생산하기 위해 나노분말 팽이 버섯에다가 수경재배한 인삼을 첨가하여 야쿠르트발효기 에서 발효한 결과 GABA 전환율은 팽이나노인삼분말 발 효군(88%) > 팽이분말 발효군(52%) > 팽이나노분말 발 효군(44%) 순으로 나타났다. 이러한 결과는 MSG를 기질 로 첨가하는 식품에서 활용할 가치가 있으리라 사료된다.

Oyster mushroom is one of mushrooms that are cultivated and consumed a lot in Korea. P. ostreatus 'Suhan(ASI2504)' is a popluar cultivar because of high quality. But it is difficult for farmers to cultivate, so an alternative cultivar of ‘Suhan’ is demanded continuously. To develop a new variety, parental strains were selected using cultivation characteristics of Pleurotus ostreatus collected home and abroad. P. ostreatus 'Gosol' was developed by the method of Di-Mon crossing between dikaryotic strain P. ostreatus 'Mongdol(ASI0633)' and monokaryotic strain derived from P. ostreatus ‘Yasan(ASI0635)' in 2014. Analysis of the genetic characteristics of the new cultivar 'Gosol' showed a different DNA profile as that of the control strain, 'Suhan’ but a similar DNA profile as those of the parental strains, ‘Yasan’ and　'Mongdol’, when RAPD(Random Amplified Polymorphic DNA) primer URP 3 was used. The optimum temperature for mycelial growth was 25°C for ‘Gosol’ and ‘Suhan’. 'Gosol' was appropriate for middle high temperature to grow, especially 13~18°C. Fruiting body production per bottle was about 124.2g. When compared to the control strain 'Suhan’, the stipe was longer and the individual weight was heavier. But the stipe and the pileus were a little thinner than those of the control strain. ‘Gosol’ was more resistant at high CO2 concentration than the control strain. This new cultivar ‘Gosol’ of Pleurotus ostreatus was characterized dark bluish gray cultivar of oyster mushroom in the color of pileus and higer yield compared to those of other cultivar ‘Suhan’. Therefore, it is suggested that this new cultivar ‘Gosol’ be substitute for ‘Suhan’ in oyster mushroom’s farms.

The aim of this study was to analyze the genetic diversity of collected strains of Hypsizygus marmoreus based on their rDNA ITS sequences. The size of ITS rDNA regions of H. marmoreus strains, collected form various regions. A phylogenetic trees based on the ITS region revealed that the strains could be classified into 4 different groups including Villosiclava virens, Hypsizygus marmoreus, Lepista irina, Lyophyllum Decastes, Lyophyllum shimeji, Pleurotus floridanus.

Hypsizigus marmoreus is commercially the most important edible mushroom in Japan. This mushroom is usually cultivatedfor a longer period (about 85~120 days) than other mushroom. In order to develop a new cultivar that has a shortened cultivationperiod, the genome analysis of this strain has been considered. This study aims to obtain parental monokaryotic strains reproducing‘Haemi’ cultivar in Hypsizigus marmoreus for reference genome sequencing. The mycelia were cultured in MCM and MYG media forvarious incubation periods. Homogenized mycelia were treated with commercial cell wall degrading enzymes to maximize protoplastsproduction yield from Hypsizigus marmoreus. The greatest number of protoplasts was obtained from mycelia cultured in MCM mediafor 3 days using Novozyme enzyme. The isolated protoplasts were grown in regeneration agar media after two weeks. Regeneratedcolonies were picked and moved on separated dishes for microscopic observation. Neohaplonts regenerated from dikayotic strainswere identified by the absence of clamp connections. We confirmed that one of monokaryotic strains is a parental strain by crossingwith an original compatible strain of ‘Haemi’ cultivar. This parental strain will be used for reference genome sequence analysis.

A new brown button mushroom cultivar, ‘Hogam’, C34 line, was made by crossing homokaryons, ASI1164-37 andASI1175-66, selected by RAPD analysis and by cultivating three times. Mycelium of ‘Hogam’ on CDA (compost dextrose agar)media grew well at 25oC. The optimum pin-heading temperature of new variety and optimum growing temperature was 14-18oC. The thickness of the mature cap and stipe were thicker than a control, ‘Dahyang’ that developed in 2010. The color ofpileus was light brown and lighter than ‘Dahyang’. Days required from casing to first harvesting were three days longer thancontrol strain, but the weight of harvested fruiting body increased by 1.35 times. ‘Hogam‘ cultivar are expected to contribute tothe diversification of domestic mushroom cultivars.

This study was conducted to obtain a growth correlation of basal information from the development of disease resistantFlammulina velutipes cultivars through back-crossing between the strains of wild-type brown monokaryon 4019-20 and thederivative of commercial quality white monokaryons 3. The two strains were selected to back-cross for further enhancing their latentattributes and growth characteristics. The parents of 4019-20×M3 back-crossed to reproduce F1, M3-Sn. Using F1, M3-Sn procuredand isolated into 94 monokaryon strains. Further examination of growth characteristics carried out by back-crossing between M3and BC1F1 from M3-n dikaryon. Monokaryon exhibited an irregular growth pattern and demonstrated to be sluggish development inthe sawdust medium. However BC1F1(M3-n) dikaryon strains confirmed mostly regular growth pattern and demonstrated ordinarygrowth in the sawdust medium. The fruitbody of BC1F1 confirmed as light-brown colour to be the dominant gene. The colourdistributions of fruitbody, BC1F1, resulted as follows; 7% of dark brown, 25% of brown , 27% of light brown, 16% of ivory and 25%of white. The ratio of the other color to white showed 3 to 1 which suggested two major genes were related to fruitbody color.

A new commercial strain “Mongdol” of oyster mushroom was developed by hyphal anastomosis. It was improvedwith hybridization between monokaryotic strain derived from Pleurotus ostreatus ASI 0627 and dikaryotic strain derived from P.ostreatus ASI 2929. The optimum temperature of mycelial growth and fruiting body development were 25~30oC and 12~18oC,respectively. When two different media including PDA (potato dextrose agar medium) and MCM (mushroom complete medium)were compared, the mycelial growth of this mushroom was faster in MCM than in PDA. Similar result was observed with thecontrol strain P. ostreatus ASI 2504. Analysis of the genetic characteristics of the new cultivar “Mongdol” showed a different DNAprofile as that of the control strain ASI 2504, when RAPD (Random Amplified Polymorphic DNA) primer URP3 and URP6 wereused. Fruiting body production per bottle was about 106 g using demonstration farms. The color of pileus was blackish gray andthe stipe was long. Therefore, we expect that this new strain “Mongdol” will satisfy the consumer’s demand for high qualitymushrooms.

‘Baekjung’ adaptable to high temperature was made by crossing between monokaryon derived from selfing of brownstrain and monokaryon derived from Korea white strain. In the condition that temperature is maintained at 10oC without lowtemperature of 4oC suppressing treatment and wrapping during cultivation period, it showed good productivity thanUri1ho(control). The optimum temperature of mycelial growth was 30oC and that of fruiting body initiation and developmentwere 14oC and 7oC, respectively. The days for the fruiting and yield were 7days and 277±11.2g per 1,100ml bottle,respectively. This variety needed high concentration of carbon dioxide up to 4,000 ppm for the good quality.