Pleurotus eryngii, an edible white-rot fungus, is widespread in Eurasia and northern Africa. It has become a major cultivated mushroom in Asia, with a current global production rate of approximately 3 × 10 5 metrictons/yr. To improve the quality or productivity through breeding, a genetic linkage map is an important component. In this study, genetic linkage map of the P. eryngii was constructed using 98 monokaryotic progeny derived from dikaryon of parental KNR2312 strain derived from haploid meiotic spores. The whole genome sequence of P5 monokaryon from P. eryngii KNR2312 strain by Next Generation Sequencing (NGS) strategy was used to design the SSR markers. 484 primers pairs were identified by SSR Locator I and tested polymorphism via PCR. A total of 241 loci were mapped using Joinmap 4.0, comprising 222 SSR markers, 2 mating type factors, and the 13 INDEL markers. The map consisted of 14 linkage groups spanning 1003 cM at an average marker interval of 4.2 cM. The mating loci, A and B were mapped on linkage groups 4 and 11, respectively. The established linkage map and the genetic information based on NGS could be used for QTL mapping of agronomic traits, marker-assisted breeding that may ultimately lead to outstanding phenotypic characteristics. [Supported by a grant from the IPET (213003-04-3-SBY20), MIFAFF, Republic of Korea.]

A new commercial cultivar ‘Hae Sal’ of Hypsizigus marmoreus was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR8047 and KNR8080. The parental strains are characterized by the property of high quality and a short period of time in cultivation respectively. The optimum temperature of mycelial growth was 25°C and that of fruiting body development was 15～16°C. The period of harvesting including primordia formation was 7.0 days shorter than that of control strain ‘Mangadak No.2’. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The yield was 117.6±23.2g/850cc plastic bottle. Analysis of the genetic characteristics of the new commercial cultivar ‘Hae Sal’ showed a different profile as that of the control strain, ‘Mangadak No.2’, when RAPD (Random Amplified Polymorphic DNA) primer was used. This new cultivar ‘Hae Sal’ of Hypsizigus marmoreus is characterized by the improved quality and a short period of time in cultivation after scratching. It would be of much help to expand the cultivation area of Hypsizigus marmoreus.

Differentiation of Pleurotus eryngii is laborious and time-consuming tasks especially in mycelial status. For development of a method for differentiation of P. eryngii cultivars, simple sequence repeats (SSR) from whole genomic DNA sequence analysis was used for genotyping and two multiplex-SSR primer sets were developed. These SSR primer sets were employed to distinguish 12 cultivars and strains. Five polymorphic markers were selected based on the genotypes. PCR with the each primer produced one to four distinct bands ranging in size from 200 to 300 bp. Polymorphism information content (PIC) values of the five markers were in range of 0.6627 to 0.6848 with an average of 0.6775. Unweighted pair-group method with arithmetic mean clustering analysis based on genetic distances using five SSR markers classified 12 cultivars into 2 clusters. Cluster I and II comprised of 4 and 8 cultivars, respectively. Two multiplex sets, Multi-1 (SSR312 and SSR366) and Multi-2 (SSR178 and SSR277) completely discriminated 12 cultivar and strains with 21 allele with a PIC value of 0.9090. These results might be useful to provide an efficient method for the identification of P. eryngii cultivars with separate PCR reactions. (This work was supported by a grant from the Gold Seed Project [Supported by a grant from the IPET (213003-04-3-WTI11), MIFAFF, Republic of Korea.]

We have used bulked segregant analysis to screen the strain-specific DNA marker associated thermophilic strain of Pleurotus eryngii. Bulked genomic DNAs of Pleurotus eryngii were amplified by randomly amplified polymorphic DNA (RAPD) using OP-A, OP-B, OP-L, OP-P, OP-R and OP-S primers to screen the strain-specific DNA marker. A unique DNA fragment of 550 bp was amplified with OP-S07 primer from the thermophilic strain and sequenced. A sequence characterized amplified region (SCAR) marker was designed on the basis of the determined sequence and named as OP-S07-1. The PCR analysis with the OP-S07-1 primer showed that this SCAR marker clearly distinguish the thermophilic strains from the control strains.

We have used bulked segregant analysis to screen the strain-specific DNA marker associated psychrophilic strain of Pleurotus eryngii. Bulked genomic DNAs of Pleurotus eryngii were amplified by randomly amplified polymorphic DNA (RAPD) using OP-A, OP-B, OP-L, OP-P, OP-R and OP-S primers to screen the strain-specific DNA marker. A unique DNA fragment of 490 bp was amplified with OP-L18 primer from the psychrophilic strain and sequenced. A sequence characterized amplified region (SCAR) marker was designed on the basis of the determined sequence and named as OP-L18-1. The PCR analysis with the OP-L18-1 primer showed that this SCAR marker clearly distinguish the psychrophilic strains from the control strains.

We have used bulked segregant analysis to screen the strain-specific DNA marker associated thermophilic strain of Pleurotus eryngii. Bulked genomic DNAs of Pleurotus eryngii were amplified by randomly amplified polymorphic DNA (RAPD) using OP-A, OP-B, OP-L, OP-P, OP-R and OP-S primers to screen the strain-specific DNA marker. A unique DNA fragment of 500 bp was amplified with OP-A11 primer from the psychrophilic strain and sequenced. A sequence characterized amplified region (SCAR) marker was designed on the basis of the determined sequence and named as OP-A11-1. The PCR analysis with the OP-A11-1 primer showed that this SCAR marker clearly distinguish the psychrophilic strains from the control strains.

A new commercial variety "KNR12-1" of Pleurotus eryngii was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR2312, KNR2594, and KNR2596. The parental strains are characterized by the property of high quality and a small number of primordia, respectively. The optimum temperature of mycelial growth was 25℃ and that of fruiting body development was 15～16℃. The period of harvesting including primordia formation was 1.0 - 1.5 days later than that of control strain Knneutari No.3 in the culling cultivation. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has a scale like as cobweb. The yield was 101.7±3.5g/850cc plastic bottle. Analysis of the genetic characteristics of the new commercial variety "KNR12-1" showed a different profile as that of the control strain, Knneutari No.3, when RAPD (Random Amplified Polymorphic DNA) primer was used. This new variety "KNR12-1" of Pleurotus eryngii is characterized by the improved storability and a small number of primordia formation after scratching. It would be of much help to mushroom cultivators in a process of culling and storage of P. eryngii.

A new cultivar "KNR11-1" of Pleurotus eryngii was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR2598 and KNR2610. The optimum temperature of mycelial growth was 25℃ and that of fruiting body development was 15 - 16℃. The period of harvesting including primordia formation of "KNR11-1" was one day faster than that of control strain KNR2312. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has the teeth of a comb. The yield was 90.4 g/850cc plastic bottle. The fruit body has a longer shelf life than control strain KNR2312 at 4℃. It is able to store up to 67.5 days in a cold room. Analysis of the genetic characteristics of the new commercial strain "KNR11-1" showed a different profile as that of the control strain KNR2312 when Random Amplified Polymorphic DNA primers were used. The new cultivar of Pleurotus eryngii is characterized by the improved storability after harvesting.

A new cultivar "KNR10-1" of Pleurotus eryngii was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR2594 and KNR2610, respectively. The optimum temperature of mycelial growth was 25℃ and that of fruiting body development was 15 - 16℃. The period of harvesting including primordia formation of "KNR10-1" was one day faster than that of control strain KNR2312. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has the teeth of a comb. The yield was 90±12.9g/850cc plastic bottle. The fruit body has a longer shelf life than control strain KNR2312 at 4℃. Analysis of the genetic characteristics of the new commercial strain "KNR10-1" showed a different profile as that of the control strain KNR2312 when RAPD (Random Amplified Polymorphic DNA) primers were used. This new variety of King Oyster mushroom is characterized by the improved storability after harvesting.

A new commercial strain "Dan Bi" of Pleurotus eryngii was developed by intra-specific crossing between monokaryotic spores derived from KNR2312 and KNR2596, respectively. The optimum temperature of mycelial growth was 25℃ and that of fruiting body development was 15 -16℃. The primordia formation of "Dan Bi" was one day later than that of control strain KNR2312. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has a scale like as cobweb. The yield was 93±4.8g/850cc plastic bottle. Analysis of the genetic characteristics of the new commercial strain "Dan Bi" showed a different profile as that of the control strain KNR2312 when RAPD primer 8001, 8002, 8003, 8004, and 8005 were used. This new variety of King Oyster mushroom is characterized by a few primordia formation after scratching. It would be of much help to mushroom cultivators in a process of culling of P. eryngii.

큰느타리버섯의 객관적인 품질기준을 마련하기 위하여 유통형태별로 자실체를 수집하여 통계적으로 본 연구실의 기준과 비교분석하고, 등급별 품질기준을 제시하였다. 즉, 키의 경우 특품(특대)120∼130, 상품(대)110∼120미만, 중품(중)80∼110미만, 하품(소)80㎜ 미만으로 두었고, 대두께는 품질별로 특품(특대)40∼45, 상품(대)30∼40미만, 중품(중)25∼30미만, 하품(소) 25㎜미만으로 정하였다. 갓직경은 절대적인 수치보다 대두께와의 비례에 의해 품질이 정해지므로 구체적인 수치를 없애는 대신 비율을 적시하였다. 특품(특대)은 갓직경/대두께의 비율이 1.6이하, 상품(대)은 1.7이하로 두었다. 무게는 특품(특대)이 95∼120, 상품(대)70∼95미만, 중품(중)50∼70미만, 하품(소)50g미만으로 설정하였다.

CO2는 버섯의 발이를 촉진하고 갓의 생성을 억제해서, 담자포자를 가지는 주름(gill)의 발달을 억제하여 버섯의 품질을 결정하는데 영향을 미친다. 본 실험에서는 큰느타리버섯의 생육에 가장 적합한 CO2농도를 구명하려고 1,600, 2,400, 3,200ppm 이하의 농도에서 버섯생육 실험하였다. 방임처리구에서 수확율은 방임조건 1,600, 2,400, 3,200ppm에서 각각 98.6, 99.3, 93.8%로 2,400ppm이 가장 우수하였고, 병당 무게에서도 2,400ppm이 가장 우수한 102.5g이 수확되었다. 품질은 2,400ppm이 6.1, 1,600ppm에서 5.5로 111% 우수하였다. 솎음처리구에서 품질은 1,600, 2,400, 3,200ppm에서 9.4, 9.5, 8.0로 2,400ppm이 가장 높았다. 병당 수확량은 1,600, 2,400, 3,200ppm에서 각각 90.7, 98.2, 77.3g 이어서 방임처리구와 마찬가지로 2,400ppm에서 많은 수확량을 보였다. 이러한 결과를 놓고 볼 때 방임과 솎음처리구의 최적 CO2농도는 2,400ppm으로 사료된다.