• Journal of Mushroom
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• v.15 no.3
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• pp.111-117
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• 2017

The mushroom species Cordyceps militaris has been studied and cultivated as a medicinal mushroom due to its multiple valuable biological and pharmaceutical activities. For breeding new strains of C. militaris, multiplex PCR assays were performed using primers specific for its mating type genes, MAT1-1 and MAT1-2. Mating types and mating status were confirmed, as evidenced by DNA bands at 233-bp and 191-bp for MAT1-1 and MAT1-2 respectively. The novel 'Dowonhongcho 2ho' was developed through mating; they were found to possess high-quality fruiting bodies when grown in artificial media. The stromata of the new strain were club-shaped, with a bright orange-red color, and measured 7.1 cm in length. They had an average cordycepin content of 0.33%. Compared to 'Dowonhongcho,' the new strain had a 7% higher yield, as well as firm fruiting bodies. The optimum temperature for mycelial growth was $20{\sim}25^{\circ}C$, and the optimum temperature for stroma development was $18{\sim}22^{\circ}C$. The fruiting bodies developed after 49.1 days from inoculation. The use of mating type molecular markers improved the breeding efficiency of the new strain 'Dowonhongcho 2ho.' Thus, they may be valuable for artificial cultivation and industrial-scale production of C. militaris with excellent characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.463-469
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• 2005

An attempt was made to analyze the factors affecting mating performance of rams in pen mating systems. Due to many types of social interactions, mating performance of rams may decrease or increase. Six intact Muzaffarnagari rams were used and divided into three dominant subordinate pairs by food and ewe competition test. For dominant rams subordinate ram became competitor and vice versa. In the first experiment, ram was exposed to ewe but the competitor ram was kept outside the pen with the facility of visibility only. In the second experiment each ram was exposed to ewe along with the competitor ram and in third experiment ram was exposed to ewes (two) along with competitor ram in observation pen. Recordings of different mating and agonistic behaviour were done in all the experiments. It was found that subordinate ram's mating behaviour was inhibited by mere presence of a dominant ram out side without physical contact. However, when ram exposed to oestrus ewe(s) along with competitor ram, both dominant and subordinate rams spent much of their time in guarding activities instead of mating. In addition dominant ram tried to curtail the subordinate ram mating by agonistic interaction like fight and butting. Different guarding activities were observed either as active or passive type depending on level of dominanace. It was concluded that in a limited space the interaction of two or more rams might affect the number of services adversely.

• Journal of Ocean Engineering and Technology
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• v.27 no.1
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• pp.9-15
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• 2013

This paper calculates the mating dynamic forces of a semi-submersible offshore structure's topside module, where a hull moored in the sea is combined with a topside module carried by a heavy lift vessel, as a mating installation method. The environmental conditions include various wave directions and wave heights, with constant wind and current speeds. Appropriate ballast and de-ballast plans for the heavy lift vessel and hull of the semi-rig should be performed in order to safely obtain these forces, whereas a fixed platform or the GBS (Gravity based structure) type of offshore structure only needs a ballast plan for the heavy lift vessel. From this paper, the allowable wave height or wave direction for the mating procedure can be investigated based on the standard DAF (Dynamic amplitude factor) of the rules and regulations.

• Tribology and Lubricants
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• v.32 no.6
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• pp.195-200
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• 2016

This study examines the wear behavior of mild steel pins mated against alloyed tool steel discs in a pin-on-disc type sliding test machine and provides specific clarification regarding the effects of disc hardness on the wear behavior of a mating mild steel pin. The analysis confirms these effects through the observation of differences in the wear rates of the mild steel pins at low sliding speed ranges. These differences occur even though the hardness of the mating disc does not affect the wear characteristic curve patterns for the sliding speeds, regardless of the wear regime. In the running-in wear regime, increasing the hardness of the mating disc results in a decrease in the wear rates of the mild steel pins at low sliding speed ranges. However, in the steady-state wear region, the wear rate of a pin mated against the 42DISC is greater than the wear rate of a pin mated against the 30DISC, which has a lower hardness value. This means that the tribochemical reactivity of the mating disc, which is based on hardness value, influences the wear behavior of mild steel at low sliding speed ranges. In particular, oxides with higher oxygen contents, such as $Fe_2O_3$ oxides, form predominantly on the worn surface of the 42DISC. On the contrary, the wear behavior of mild steel pins at high sliding speed ranges is nearly unaffected by the hardness of the mating disc.

• Biomedical Science Letters
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• v.2 no.1
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• pp.109-114
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• 1996

A study was conducted to evaluate isolation rate and distribution of mating type of M.gypseum complex Arthroderma(A.) gypsea and A.incurvata. Seventeen(17) strains were isolated from children patients and sixty(60) strains were from elementary school playgrounds, flower beds, and childrens playgrounds in Taegu area. The strains were crossed with test strains of A.gypsea and A. incurvata which were provided by Tokyo university. The results were summarized as follows; Of seventeen(17) strains, thirteen(13) were isolated from male children and ten(10) were A.incurvata and three(3) A.gypsea, and four(4) were from female children and all iou, strains were A.incurvata. Face(Tinea facial) was more frequently affected to compare with other clinical type. Of seventeen(17) strains isolated from patients, six(6) were A.incurvata "+" type and eight (8) were "-" type, and two(2) were A.gypsea "+" type and one(1) was "-" type. Of sixty (60) strains isolated from soil, sixteen (16) were A.gypsea "+" type and fifteen(15) were"-" type. and fifteen(15) were A. incurvata "+" type and fourteen(14) were "-" type.) were A. incurvata "+" type and fourteen(14) were "-" type. &"-&" type.t; type.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.25-31
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• 2003

Changes of control effect of metalaxyl to potato late blight caused by Phytophthora infestans were examined in potato fields in 2001 and 2002. Control efficacy of metalaxyl was similar to those of dimethomorph and ethaboxam. About 4.9% of the fungal isolates exanlined in 2001 were resistant, 87.8% were intermediate, and 7.3% were sensitive to metalaxyl. Among the isolates collected in 2002, 20.1 % were resistant, 75.5% were intermediate, and 4.3% were sensitive to the chemical. However, most of resistant isolates were isolated from Pyongchanggun Hoenggae area. Eighty eight isolates collected in 2001 were all A1 mating type, while both A1 and A2 mating types were found in 2002. About 85.6% of the isolates collected in 2002 were A1 mating type, but all the rest (A2 mating type) was isolated from Hoenggae area. Increased control efficacy of metalaxyl to potato late blight might be caused by the increase of moderately resistant and sensitive isolates with decreasing the resistant isolate, and the decreased population of A2 mating type which is resistant to metalaxyl.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.98-102
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• 2003

Metalaxyl sensitivity related with distribution feature of mating type was characterized far Phytophthora capsici population, totally 433 isolates of the red-pepper pathogen collected from 75 pepper fields in Korea from 1995 to 1998. At the concentration of metalaxyl $2{\mu}g/ml$, inhibition rate of mycelial growth of P. capsici isolates was 68.2% in average compared to control, and 28.6% isolates in average were estimated as resistance to the chemical. Isolates of field unit with a single mating type revealed similar level of sensitivity to metalaxyl and showed sensitive or resistant in most field units. However, isolates of field units with both mating types revealed diverse sensitivity level to the chemical and various occurrence ratio of metalaxyl sensitive : resistant in each field unit. Results indicated that different levels of metalaxyl sensitivity of P. capsici population in Korea seem to be closely related with occurrence ratio of A1 : A2 mating type of each field.

• Research in Plant Disease
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• v.16 no.3
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• pp.274-278
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• 2010

Potato late blight caused by Phytophthora infestans was the most constrain disease at potato cultivation areas. The mating type distribution and fungicides response of P. infestans were investigated to elucidate the changes of pathogen from Gangwon province. On the fungal isolates in 2006, 58.7% were A1 mating type and 41.3% were A2 mating type. In 2007, A1 mating type isolates increased to 93.3% and A2 mating type isolates were collected from Jinbu areas as much as 6.7%. About 234 isolates analysed for metalaxyl response, the results was resistance 73.7%, intermediate 18.8% and sensitive 7.5% in 2006. And it was resistance 59.4%, intermediate 4.0% and sensitive 36.6% in 2007. It meant that mating type distribution and fungicide response were very different over the collection sites. Minimal inhibition concentration (MIC) of dimethomorph examined with 126 isolates in 2006 and 106 isolates in 2007. MIC over $1.0\;{\mu}g/ml$ was 56.3% in 2006 and it was 3.8% in 2007. The average $EC_{50}$ value of P. infestans was $0.37\;{\mu}g/ml$ in 2006, but it decreased to $0.12\;{\mu}g/ml$ in 2007. Fungicides response and pathogenesis of P. infestans should be monitored continuously to enhance the chemical efficacy at potato fields.

• Research in Plant Disease
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• v.8 no.1
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• pp.41-44
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• 2002

Two species of Phytophthora were isolated from infected fruits of jujube. Among 18 isolates collected, 6 were identified as P. nicotianae and 12 as P. patmivora on the basis of their mycological characteristics. The former produced no caduceus, ovoid to spherical sporangia in contrast to caduceus, ellipsoid, and broadly avoid to spherical ones of the latter. These two species were shown to be heterothallic and markedly papilate, chlamydospores abundant, and Al mating type. They skewed strong pathogenicity to fruits of jujube and pear while no symptom was produced on apple fruit by artificial inoculation. This is the first report of juiube fruit rot caused by P. ninotianae and P. palmivora in Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.725-730
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• 1992

The internal invertase was purified from cell free extract of Rhodosporidium toruloides IFO 0559-M-919 by acid precipitation, ion-exchange chromatography and gel filtration to the unique enzyme protein on disc electrophoresis. We have found out that molecular weight of purified internal invertase was 90,000 by gel filtration and the purified enzyme was protein with 4 homogeneous subunits appearing as single band of 22,000daltons on SDS-polyacrylamide gel electrophoresis.