• Journal of Sericultural and Entomological Science
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• v.9
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• pp.67-87
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• 1969

1. Objectives and Importance. Many silkworms have been damaged by nuclear polyhedrosis virus diseases thoughout the country every year causing a decease in cocoon production by approximately ten per cent per year. The damage caused by the infections virus has occured in spite of complete disinfection. In this respect, it is well known it is impossible, at the present time, to protect the silkworm from these virus infections through chemical and physical control methods. Therefore, this author has attempted to solve this urgent problem from the view point of heredity and breeding, discovering the different resistances and heritabilities among 120 stains collected from throughout the country, and selecting the ones with highest resistance for the basic materials in the silkworm breeding. 2. Results of work 1) The strains with strong resistance to the nuclear polyhedrosis virus diseases are N$_4$, N$\sub$15/, N$\sub$48/, C$\sub$55/ and Em. the log ED$\sub$50/ values of them vary between 0.799 and 1.611. The susceptible strains are N$\sub$20/, C$\sub$62/, N$\sub$76/, N$\sub$79/ and C$\sub$108/, the log ED$\sub$50/ values of them vary between 5.159 and 7.258. (Reference Table 4) The Japanese strain with a log ED$\sub$50/, value of 3.770 is the strongest, followed by the Chinese strain with a log ED$\sub$50/ value of 3.564. The weakest is the European strain with a log ED$\sub$50/ value of 3.3381. The direction coefficient of the regression equation of the susceptibility varies between 0.1 and 0.6, the uniformness of the resistance of the preserved strains of this country is comparatively low. The hereditary henomena of the resistance of each strain and the conerete method of its application for silkworm breeding main the subjects for later studies. 2) The content of water and ash in silkworm has not been correlated with the capability for resistance to the virus diseases(Reference. Table 8). but it is very significantly correlated with mortality rate (in common reaning). In the case of the silkworms which have just completed the fourth moulting the content of water and ash is not related to the mortality rate. In the case of the silkworms which have just completed the third moulting, however, the water( +0.326) and ash (+0.362) registered a high significance. The ash content in the first ($\div$0.520) and second ($\div$0.386) moults is highly significant but water content in both cases is not significant (Reference Table 7). 3) The No. 205 strain proved to be the best in character among the various F$_1$ hybrids. No. 204 was very good in strength but a little lower in cocoon character than the control. No. 212 was a little low in coccon character and mortality was average, but the cocoon harvest was the best among all the varieties offered for (Reference Table 9). 4), In short, the above mentioned strains which are known to have strong resistance to the virus disease are expected to provide basic data for breeding strong varieties. It is proposed that continued research should be conducted on the characteristics of various strains for a satisfactory preservation of various characteristics.research should be conducted on the characteristics of various strains for a satisfactory preservation of various characteristics.

• Journal of Mushroom
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• v.15 no.2
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• pp.84-87
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• 2017

Although ear mushroom (Auricularia auricula-judae) is cultivated worldwide, there are a limited number of commercial cultivars in Korea. Recent increase in the import of ear mushroom from China threatens the domestic farming. The present study introduces a new thermotolerant cultivar of ear mushroom, designated 'Hyeonyu', developed by mating monokaryons obtained from JBAA11 and CAA1 strains. The optimal growth temperature for Hyeonyu was 26-36?. The periods of primordia formation and fruit-body growth were 27 and 15 days, respectively. The average mushroom yield per bag (1 kg) was 350 g. Random amplification of polymorphic DNA (RAPD) analysis with OPA1 and OPA7 primers identified polymorphic DNA bands between the control, the new variety Hyeonyu, and a Chinese variety.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.185-191
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• 2012

For initiation of resistance breeding program of the red pepper, 21 PR ($Phytophthora$ resistance) cultivars, 36 cultivars collected from USA and 'Supermanitta' which is a susceptible cultivar against phytophthora blight were assayed against phytophthora blight, powdery mildew, and anthracnose. For seedling assay of phytophthora blight, three different mating type strains of $Phytophthora$ $capsici$ were used (A1, A2, Sterile). The result showed that most of the pepper of PR cultivars were resistance or moderately resistance at each mating type. 'Yeokganghongjanggun' was resistant to all three $P.$ $capsici$ strains and 'PR-Datta' and 'PR-Manitta' were resistant or moderately resistant at each type. In case of the collected cultivars, 'NuMex J.E.Parker', 'Omni Color', and 'SCM334' were resistant to all the three types and some cultivars including 'Sweet Banana' and 'Tabasco' were moderately resistant to each type fungi. 'Orange Habanero' and 'Black Cuban' were resistant to powdery mildew and 'Supermanitta' and 'PR Keumdong' were moderately resistant, while 'Santa Fe Grande', 'NuMex Pinata' and 'Puya' were very susceptible. In the case of anthracnose, 'Aji Limon' and 'Capsicum baccatum var. pendulum 3-4' were resistant and 'Pobalno', 'Omni Color', 'Negro', 'Mesilla', 'Mulato', 'Bhut Jolokia', 'Big Dipper', 'Black Cuban', 'NuMex Pinata', and 'NuMex Big Jim' were moderately resistant. The most PR cultivars except 'Taesan' were susceptible or very susceptible. These resistant individuals identified through this experiment can be used as sources of resistance to pepper pathogens in the future breeding programs.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.5
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• pp.603-621
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• 2017

The current review focuses on characterization and conservation efforts vital for the development of breeding programmes for indigenous beef cattle genetic resources in Southern Africa. Indigenous African cattle breeds were identified and characterized using information from refereed journals, conference papers and research reports. Results of this current review reviewed that smallholder beef cattle production in Southern Africa is extensive and dominated by indigenous beef cattle strains adaptable to the local environment. The breeds include Nguni, Mashona, Tuli, Malawi Zebu, Bovino de Tete, Angoni, Landim, Barotse, Twsana and Ankole. These breeds have important functions ranging from provision of food and income to socio-economic, cultural and ecological roles. They also have adaptive traits ranging from drought tolerant, resistance to ticks and tick borne diseases, heat tolerance and resistance to trypanosomosis. Stakeholders in the conservation of beef cattle were also identified and they included farmers, national government, research institutes and universities as well as breeding companies and societies in Southern Africa. Research efforts made to evaluate threats and opportunities of indigenous beef cattle production systems, assess the contribution of indigenous cattle to household food security and income, genetically and phenotypically characterize and conserve indigenous breeds, and develop breeding programs for smallholder beef production are highlighted. Although smallholder beef cattle production in the smallholder farming systems contributes substantially to household food security and income, their productivity is hindered by several constraints that include high prevalence of diseases and parasites, limited feed availability and poor marketing. The majority of the African cattle populations remain largely uncharacterized although most of the indigenous cattle breeds have been identified.

• Journal of Mushroom
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• v.18 no.3
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• pp.214-220
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• 2020

We undertook a breeding program to produce a white button mushroom cultivar with high temperature tolerance in preparation for climate change. The results were as follows. The strains KMCC00540, KMCC00591, and KMCC00643 were selected, and homokaryons were selected and hybrids were identified with ISSR and SSR markers, respectively. The selected hybrids were cultivated in three repetitions at a temperature of 20-25 ℃ and a humidity of 80% or higher. The variation in agricultural traits and fruiting body characteristics was least in the Abs4-2016-121 strain. This line is a hybrid of KMCC00591 and KMCC00875, and field experiments at Gyeongju and Buyeo farms found that the Abs4-2016-121 line has high fruiting body with hardness and delayed opening of pileus at high temperatures, so it was bred as a high-temperature cultivar named 'Hadam'.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.115-120
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• 2002

Xanthomonas axonopodis pv. glycines, the causal agent of bacterial pustule of soybean, induces hypersensitive response (HR) in a non-host plant, hot pepper (Capsicum annuum). A wild-type strain (8ra) and its non-patho-genic mutant (8-13) of X. axonopodis pv. glycines were inoculated into the pepper leaf tissues and their subcellular responses to the bacterial infections were examined by electron microscopy. Intrastructural changes related to HR were found in the leaf tissues infected with 8ra from 8 h after inoculation, characterized by separation of plasmalemma from the cell wall, formation of small vacuoles and vesicles, formation of cell wall apposition, and cellular necrosis. No such responses were observed in the tissues infected with the mutant. In 8ra, the bacterial cells were attached to the cell walls, with the cell wall material dissolved into and appearing to encapsulate the bacterial cells. The bacterial cells later became entirely embedded in the cell wall material. On the other hand, in 8-13, the bacterial cells were usually not attached tightly to the plant cell wall, and no or poor encapsulation of the bacteria by the wall material occurred, although these were encircled by rather loose wall materials at the later stages.

• Journal of Mushroom
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• v.12 no.3
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• pp.187-192
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• 2014

In order to breed a new P. eryngii cultivar with high temperature tolerance trait to cope with climate change, strains and cultivars were characterized at $20^{\circ}C$ that is $5^{\circ}C$ higher than normal condition followed by screening for the characteristics such as required days to harvest, quality and yield. Monokaryons from the selected strains were crossed. $Da-32{\times}KNR2322-15$ derived from the crosses between KNR2322 having characteristics of short growing day and Da($Ga5Na5-4{\times}KNR2312-7$) having charateristics of high guality and yield at $20^{\circ}C$, showed 14.9 days for harvest, 120.6 g yield, and 7.0 quality in the first trial. The strains were named as Taeyangsongi and cultivated on a large scale to compare with Kenneutari No. 2 at a mushroom farm. Yield of Taeyangsongi (109 g) was significantly different(P=0.001) from Kenneutari No.2. Quality of the new (6.6) and the reference cultivar (3.5) was also statistically different (P=0.001) The brightness of pileus of Taeyangsongi (59.5) was 10 points less than the reference cultivar due to which it has an inability to bear high temperature stress. Thus, PCR reactions with URP2 discriminated between Taeyansongi and reference cultivars (Keneutari No. 2 and Aeryni).

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.177-185
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• 2018

The cultivation characteristics of 26 wild strains of Lentinula edodes were investigated for their use as breeding material. Strains NIFoS 68, 136, 1521, 1651, and 2064 showed an above average mycelial growth on potato dextrose agar at 10, 20, and $30^{\circ}C$. NIFoS 411 showed the lowest mycelial growth at $20^{\circ}C$, but the highest growth at $30^{\circ}C$. The rate of weight loss of L. edodes cultivated on sawdust (2 kg) ranged from 13.5 to 47.5%, with the highest rates showed by NIFoS 50 (47.5%), NIFoS 128 (34.5%), and NIFoS 54 (34.4%). Fruiting bodies were produced in nearly all (24/26) strains and productivity ranged from 3 g to 446 g/2 kg medium. Temperature was not significantly correlated with mushroom production or mycelial growth. Larger weight loss correlated strongly with fruit yield. In terms of production, NIFoS 50 (446 g), NIFoS 952 (435 g), and NIFoS 53 (421 g) were useful as breeding material. The NIFoS 667 strain was superior in terms of morphology. NIFoS 670 showed the characteristic yellowish-brown color of fruiting bodies.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.59-64
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• 1990

The present study was conducted in order to elucidate the asymptomatic carrier state of dermatophytes on the laboratory rodents in Korea during the period from August 1986 to April 1987. A total of 988 laboratory rodents, comprising 393 albino rats, 285 albino mice, 238 guinea pigs and 72 hamsters, were randomly selected for the isolation of dermatophytes from 6 research institutes and 2 breeding farms. And the mating experiments were performed to identified the perfect states of Trichophyton mextagrophytes isolated from albino rats. Dermatophytes were recovered from 94 of 393(23.9%) albino rats and from 3 of 5 colonies. Isolation rate of each colony was 38.4%, 32.0% and 9.8%, respectively, and the albino rats over 2 months old(28.2%) were higher than below 2 months old(2.9%) in the isolation rate of dermatophytes. Among 94 strains of dermatophytes isolated from albino rats, all the strains were identified T mentagrophytes, except 1 strain of Microsporum gypseum, and its perfect states were Arthroderma $vanbreuseghemii^+$.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.51-57
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• 1990

In order to know the prevalence of S. hyicus subsp hyicus in pigs, attempts were made to isolate the organism from 549 healthy adult pigs, 277 healthy suckling piglets and 17 piglets with exudative epidermitis from April 1988 to January 1989 in Chinju, Korea. Also determined was antibiotic susceptibility of the isolates. Isolation rates of S. hyicus subsp. hyicus from adult pigs and suekling piglets were 27.0% and 53.1%, respectively. The organism was isolated predominantly from abdomen (10.9%) of adult pigs and external ear (31.6%) of suckling piglets. Isolation rates of the organism from piglets of different age group were in order of prevalence of 1(82.1%), 3(74.0%), 2(54.7%), 4(52.9%), 5(15.2%) and 6(5.7%) post-natal weeks. All of 489 isolates were sensitive to gentamicin, kanamycin and cephalexin but 23.7~79.6% of the strains were resistant to erythromycin, penicillin G and tetracycline. The 49.2% of these resistant strains exhibited multiple drug resistance. The drug resistant patterns most frequently encountered were PG TC EM(10.7%) in triple pattern, PG TC(23.0%) in double pattern and TC(44.4%) in single pattern.