A new spore-less cultivar Lentinula edodes ‘Daedam’ was bred from monokaryotic strains of ‘LE15401-24’ and ‘LE192118-10’. The optimum temperature for mycelial growth of ‘Daedam’ on potato dextrose agar was 22~25oC. Total cultivation period of the new cultivar, from inoculation to its first harvest, was 134 days, similar to that of the control cultivar ‘Hwadam’. Total yield of ‘Daedam’ was 222g per 3kg substrate, and was lower than that of control cultivar(266.0g). The fruiting body of ‘Daedam’ had a thick and small pileus and a longer stem compare to control cultivar. As a result of a analyzing the productivity of ‘Daedam’ on the different substrate types, the biological efficiency was 26.7% in the 1.2kg cylindrical substrate(CS), which was higher than that of the 3kg rod-type substrate(RS). 'Daedam' had a similar yield compared to 'Hanacham' in first fruiting body production, but the cultivation period was 40 days shorter. Therefore, 'Daedam' can only harvest fruiting bodies once, it is thought that it can be used as spore-less oak mushroom cultivar for short-term cultivation instead of 'Hanacham' in mushroom farms.

국내 표고 품종 다양화로 버섯산업 경쟁력을 높이고자 ‘참아람’과 청흥버섯영농조합 보유균주인‘E140025’을 이용하여 교잡육종법을 통해 ‘청흥1호’를 육성하였다. 자실체 특성 결과 대조품종 보다 갓직경은 작고, 대길이는 길고, 대가 굵어 개체중이 무거웠다. 초발이기간은 ‘청흥1호’ 24일, ‘설백향’4일, ‘산조701호’ 8일로 발이까지 대조품종보다 20일정도 늦었다. 자실체 수량은 가장적게 나타났지만, 유효수량은 ‘청흥1호’ 6,498 g ‘설백향’ 4,290 g, ‘산조701호’ 5,022 g으로 가장 높았다. URPPrimer를 이용한 다형성검정을 통해 6개의 Primer에서 모본과 다른 PCR 밴드를 확인하였다. 이상의 결과, 재배기 간이 길지만 개체중과 유효수량이 우수한 무포자 신품종을 육성하였다.

For heaths and vitality Cordyceps sinensis has been widely used as an important medicinal mushroom. C. militaris is popular for its substitute and can be cultivated artificially. Its new strains have been improved by crossing single spore strains. A bipolar heterothallic fungus, C. militaris has two strains of compatible mating types and they can be differentiated by crossing, fruiting body formation ability and the production of perithecia. Each isolate was determined to be monokaryotic or dikaryotic on the basis of perithecial formation by fruiting tests. This process was also carried out by molecular markers for the detection of two opposite mating types or F1 hybrids using two sets of primers specific for C. militaris amplifying a 191-bp fragment for MAT1-2 and 233-bp fragment for MAT1-1. Therefore the crossing of two compatible mating types resulted in well-developed perithecial fruiting bodies and their crossings were confirmed by the PCR assays for the rapid and specific detection of both MAT1-1 and MAT1-2. This results showed that molecular markers provide an efficient alternative for identification of hybridal status or mating types in the breeding program for artificial cultivation and industrial-scale production of C. militaris.

The effect of pt-I values of 6.5, 6.0, 5.0, and 4.0 on spore germination of Bacillus cereus (B. cereus) was investigated at water activity (a%) values of 0.98, 0.96, 0.94, and 0.90 in a controlled medium at 30°C for 7 days. The best condition for germination of spores of B. cereus was observed at pH 6.5 with aw 0.98. No matter what combination of a and pH is used, a complete inhibition of spore germination was achieved at either a,.. value of 0.90 or pH value of 4.0. Spore germination was also delayed or inhibited at aw 0.98 with pH 4.0, aw 0.96 with pH 5.0, and aw 0.94 with pH 6.5, 6.0, 5.0, or 4.0. The results indicate that the combined inhibitory effects of pH and water activity on the germination of B. cereus spores in controlled medium could be applied to food preservation.

Agaricus bisporus is a nutritious edible fungus that is cultivated worldwide. Because of its secondarily homothallic life cycle, 90% or more of the basidia lining the gills at fruit bodies are predominantly two-spored, with each spore receiving two of the four meiotic nuclei. Such homothallic system results in scarcity of monokaryotic basidiospores in its progeny but the availability of uninucleate self-sterile homokaryons is a pre-requisite for producing hybrids in breeding program. This experiment screened 64 single spore isolates collected from CN0210-021, which is white button mushroom cultivated in Chungnam area. They were germinated on PAD meduium at 25℃. After 30 days of incubation colony diameter and morphology type of each isolates was determined. Based on growth rate, 5 strains showing very slow growing morphology than that of parental heterokaryotic strain were selected. Out of 5 slow growing isolates, 2 of them fruited and the rest 3 isolates did not fruit, which were considered as putative homokaryons. These data will provide the outcrossing sources that could be used in commercial breeding programs later. However, in the identification of homokaryotic strains, there is no direct morphological distinguishing features such as a clamp connection that would permit the reliable sorting between homokaryons and heterokaryons. Traditional method to verify a homokaryon thorough the fruiting trial is also time-consuming and not perfect. Therefore, to accelerate the breeding of Agaricus bisporus, quick and reliable methods such as molecular markers to identify the infrequent homokaryons from heterokaryons are needed to be carried out.

The effect of gamma irradiation on the survival of spore bacteria was investigated in frozen cells (-18℃) with 0.1 M phosphate buffer and inoculated cells in beef. In the case of the frozen cells at log phase, the radiation D_(10) and 12D_(10) values were 0.29 kGy and 3.48 kGy in Bacillus subtilis, 0.39 kGy and 4.68 kGy in Bacillus cereus and 0.46 kGy and 5.52 kGy in Clostridium perfrigens. And inactivation factors were 6.52-10.34 and 10.87-17.24 at the dosage of 3 kGy and 5 kGy, respectively. The radiosensitivity of inoculated cells in beef showed the D_(10) value of 0.59-0.76 kGy, the 12D_(10) value of 7.08-9.12 kGy, and inactivation factors of 3.95-8.47. The radiosensitivity of the frozen cells was higher than that of inoculated cells in beef.

D_(10) values obtained for radiation alone in Bacillus subtilis and Clostridium perfrigenes were 0.35-0.48 kGy in vegetative cells, and 2-2.08 kGy in spores, respectively. Irradiation dose of 24 kGy completely inhibited spores. In the case of heat treatment, D_(50, 60) values ranged from 10 to 14 minutes in vegetative cells, and D_(70, 80, 90), values ranged from 10 to 140 minutes in spores. In the case of combined treatment with heat and radiation, D_(10) values ranged from 1 to 1.25 kGy in vegetative cells, and from 3.42 to 3.61 kGy in spores. Thus, resistance of cells to gamma radiation did not seem to be influenced by pre-heating.

콩의 흑색뿌리썩음병을 일으키는 Cylindrocladium crotalariae은 감자한천배지와 콩의 조직을 함유한 한천 배지를 서로 다르게 Water potential를 조절하여 이 병원균을 접종한 결과 균사신장과 대형분생포자형성은 -14bars에서 좋았고 에서는 -100bars 에서는 -80bars 에서는 -64bars에서 균사신장이 중지되었으며 포자형성도 -64bars에서 중지되었다. 자낭각과 미소균핵형성은 소금을 첨가하지 않은 -1.4나 -3.0bars에서 잘 되었고 이 균에 대한 포자발아율은 -1.4bars에서 -20bars의 모든 Water potential에서 똑 같이 좋았고 -20bars에서 Water potential이 낮아지므로 발아율이 떨어지다가 -60bars에서 억제되었다.

Background : Ginseng is perennial, frequently damaged by various diseases and insect pests, due to this, quantity and quality decreases. Particularly, Alternaria blight greatly damages the stem in its germination and the leaves after leafing. Here, this research conducted a test by investigating the control effect of lime-sulfur mixture in the market on 5 ginseng Alternaria blight, in order to utilize it as the disease control measure for disease and pest for eco-friendly cultivation of ginseng. Methods and Results : This research investigated the control effect of 5 types of lime-sulfur mixture in market on ginseng spotting disease by distributing the solvents to 5-years ginseng by 100 times and 200 times on April 29, May 15, and May 27. Also, this research investigated spore germination inhibition effect on Alternaria panax, Colletotrichum sp. and Botrytis cineria spore germination inhibition effect was investigated with spore germination inhibition ratio by manufacturing 100 times’ culture and 200 times’ culture per lime-sulfur mixture medium. There were two materials among 5 lime-sulfur mixture products to control over Alternaria blight using eco-friendly ginseng material, which didn’t damage during the leafing period of ginseng, and this research selected Sulfur 153, effective for Alternaria blight. Sulfur 153 was effective for Alternaria blight control due to its 82.2% control effect when treating by 200 times. Sulfur 153 was effective for spore germination inhibition of Alternaria panax, Colletotrichum sp. and Botrytis cineria and the rates of spore germination inhibition were 71.5, 100, 19.5% respectively. Conclusion : There were 2 materials among 5 lime-sulfur mixture products to control over Alternaria blight using eco-friendly ginseng material, which did not damage leafing period, and sulfur 153 was selected as the material effective for Alternaria blight. Sulfur 153 appeared to suppress germination of spore of Alternaria panax and Colletotrichum sp.

This study was conducted to determine the optimal conditions of growth medium, temperature, and light quality for efficient propagation of Lygodium japonicum spores. The rate of spore germination and prothalium development was high in Knop and 1/8MS and 1/4MS media, which had low mineral content; in particular, the germination rate exceeded 74%, and the germinated spores developed into heart-shaped prothallia. However, in Knop‘s medium with the lowest mineral content, a rapid prothallium senescence was observed; in 1/4MS medium, prothallium development was delayed. Germination rate increased with the increase in temperature and reached its maximum, 86.7%, at 30°C; however, at this temperature, the prothallia were thinner and abnormal development of rhizoids was observed compared to normally developed prothallia and rhizoids at 25°C. Therefore, the results suggested that the optimal temperature for L. japonicum spore germination was 25°C. The rate of germination was also measured under different light conditions, and the highest rate of 90.6% was observed under LED red light compared to fluorescent (77.2%) or LED blue (5.4%) lights. The germinated spores developed into heart-shaped prothallia under LED red light; however, 15 days after seeding, prothallium development decreased and the became elongated. In contrast, a normal and continuous development of heart-shaped prothallia was observed under fluorescent light.

Background : This study was conducted to determine the optimal conditions of growth medium, temperature, and light quality for efficient propagation of Pyrrosia petiolosa spores. Methods and Results : P. petiolosa spores were collected from Andong-si area in February 2015, and the spores were subjected to a careful selection process. The selected spores were stored at the Korea National Wild Plant Seed Bank (4℃, RH 40%) and used as our experimental materials (GR0000182302). The spore germination rate and prothalium development were high in Knop media (24.5%), which had low mineral content. The germination rate increased with the increase in temperature and reached its maximum, 24.5%, at 25°C. The germination rate was also measured under different light conditions, and the highest rate of 28.7% was observed under LED blue light compared to fluorescent lights (24.5%). The germinated spores developed into heart-shaped prothallia under LED blue light; however, 3 weeks after sowing, prothallium development decreased compared to fluorescent lights. Conclusion : In conclusion, the optimal P. petiolosa In vitro propagation method include spore germination on Knop medium at 25°C under LED blue light, and the change in light source to fluorescent light 3 weeks after sowing for prothallium formation and proliferation.