• Journal of Mushroom
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• v.18 no.4
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• pp.297-302
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• 2020

Five varieties of mushrooms, including Sae-do, were examined using farm field tests to determine their morphological characteristics and quality by performing harvest flush. Considering the cultivation characteristics of the varieties studied, the parts related to mushroom generation and production showed almost similar characteristics. Overall, the mycelial forces were similar; however, in the evaluation of plantation tests performed by farmers, "saedo" was found to be the strongest and "saehan" was considered to be the weakest. Weights of fruiting bodies were related more for compost status and regimen of use than for breeding, and it was difficult to distinguish between the weights of fruiting bodies of the varieties studied. Regardless of the variety, pileus diameter, pileus thickness, and stem length of Dalseong-gun, Yongin-si, and Boryeong-si decreased as the harvest flush progressed. However, stem thickness tended to increase in the second and third flush compared to that in the first flush, regardless of the variety. However, the Gyeongju-si farms could not identify any trends attributable to varieties and harvest flushes. The pileus size and stem length of the fruiting bodies of varieties from Buyeo farms decreased with the progression of the harvest flush. However, pileus thickness and stem thickness did not show any specific tendency of growth among the varieties studied. The differences in the morphological characteristics of mushroom varieties in each harvest cycle are expected to be caused by differences in the supply of nutrients in the medium, the quality of the compost used, and the cultivation environment rather than the variety.

• Animal Bioscience
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• v.35 no.1
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• pp.13-21
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• 2022

Objective: The aim of the study was to evaluate the influence of gene polymorphisms and nongenetic factors on the somatic cell score (SCS) in the milk of Holstein (n = 148) and Simmental (n = 73) cows and their crosses (n = 6). Methods: The SCS was calculated by the formula SCS = log₂(SCC/100,000)+3, where SCC is the somatic cell count. Polymorphisms in the casein alpha S1 (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3), beta-lactoglobulin (LGB), acyl-CoA diacylglycerol transferase 1 (DGAT1), leptin (LEP), fatty acid synthase (FASN), stearoyl CoA desaturase 1 (SCD1), and 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6) genes were genotyped, and association analysis to the SCS in the cow's milk was performed. Further, the impact of breed, farm, year, month of the year, lactation stage and parity on the SCS were analysed. Phenotype correlations among SCS and milk constituents were computed by Pearson correlation coefficients. Results: Only CSN2 genotypes A¹/A² were found to have significant association with the SCS (p<0.05), and alleles of CSN1S1 and DGAT1 genes (p<0.05). Other polymorphisms were not found to be significant. SCS had significant association with the combined effect of farm and year, lactation stage and month of the year. Lactation parity and breed had not significant association with SCS. The phenotypic correlation of SCS to lactose content was negative and significant, while the correlation to protein content was positive and significant. The correlations of SCS to fat, casein, nonfat solids, urea, citric acid, acetone and ketones contents were very low and not significant. Conclusion: Only CSN2 genotypes, CSN1S1 and DGAT1 alleles did show an obvious association to the SCS. The results confirmed the importance of general quality management of farms on the microbial milk quality, and effects of lactation stage and month of the year. The lactose content in milk reflects the health status of the udder.

• Korean Journal of Animal Reproduction
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• v.10 no.1
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• pp.49-57
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• 1986

Studies were conducted to investigate the relationship between hormone leveles and nutritional levels for improving performance of Cheju native cattle. In June 1984 a trial was initiated using 8 Cheju native calves after weaning, fed at two su, pp.ementary feeding levels (NRC 100% and 70%). The body weight, breedng performence, change in progesterone level during pregnancy and estrus cycle were evaluated. Mean body weight at 6 months of age was 155kg when fed 100% NRC ration but it was only 137kg when heifers received the 70% NRC ration. At 10, 15 and 20 months of age the body weight was 66, 160 and 115kg, respectively, showing that heifers fed the standard ration gained weight rapidly (P<0.01). Average size of the lefe ovary in the standard group was 2.1${\times}$1.6cm and right ovary was 2.6${\times}$1.8cm. However in the restricted feeding group the ovaries were found to be smaller. Diameter of graffian follicles showed a similar tendency to ovarian size in the two groups. The first oestrus in the standard feeding group a, pp.ared at 14.6 months when body weight was 265kg. Age at first calving was on average 28.9 months at a body weight of 436kg. On the other hand when heifers were fed the restricted ration the first oestrus a, pp.ared at 23.0 months at a body weight of 250kg. Average age at first calving was 38.9 months which was 10 months later than the average in the standard feeding group (P<0.01). In standard feeding group the progesterone level was 2.0ng/ml at two weeks after pregnancy and gradully increased up to 4 weeks and peaked at 18 weeks. This peak (6.4-6.5ng/ml) was maintained up to 24 weeks when progesterone level decreased until it reached 2.1ng/ml at the end of pregnancy. In the restricted group progesterone level up to 16 weeks followed a similar pattern to the standard group but there was a tendency in the restricted group to have lower progesterone levels(P<0.01). The standard and srstricted groups showed similar patterns of progesterone concentration during the oestrus cylce. There were no statistically significant differences in progesterone levels between standard and restricted groups but there was variation between induvidual animals.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.263-274
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• 2022

Lentinula edodes is an important commercial mushroom and there have been several reports of viral infections in L. edodes. Two mycoviruses (LeV-HKB and LeNSRV1) were detected in Sanbaekhyang (NIFoS 2778) and Taehyanggo (NIFoS 4317), the sawdust-cultivated commercial strains. The vertical transmission rates of the viruses were investigated by detecting the viruses in 80 monokaryotic strains derived from basidiospores isolated from the fruiting bodies of each strain. Most of the monokaryotic strains were infected with the virus and the two viruses showed different levels of meiotic stability, with LeV-HKB showing higher meiotic stability than LeNSRV1. Therefore, it seems that the vertical transmission mechanism of mycoviruses is different depending on the virus species. We also examined the mycelial growth rate of the monokaryotic strains and compared the growth rate according to virus infection status. Although there was no statistically significant correlation between viral infection and mycelial growth rate, we found that the average growth rate was reduced by additional virus infection. We expect our data to contribute to a greater understanding of the mechanism of the vertical transmission of mycoviruses, and promoting breeding using virus-free monokaryotic strains.

• Animal Bioscience
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• v.37 no.5
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• pp.952-961
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• 2024

Objective: Stocking density (SD) is an important issue in the poultry industry, which is related to the production performance, intestinal health and immune status. In the present study, the effects of SD on the metabolism and homeostasis of uric acid as well as the related functions of the liver and kidney in ducks were examined. Methods: A total of 360 healthy 56-day-old Shan-ma ducks were randomly divided into the low stocking density (n = 60, density = 5 birds/m²), medium stocking density (n = 120, density = 10 birds/m²) and high stocking density groups (HSD; n = 180, density = 15 birds/m²). Samples were collected in the 3rd, 6th, and 9th weeks of the experiment for analysis. Results: The serum levels of uric acid, lipopolysaccharide and inflammatory cytokines (interleukin-1β [IL-1β], IL-8, and tumor necrosis factor-α [TNF-α]) were increased significantly in the HSD group. Serious histopathological lesions could be seen in both the livers and kidneys in the HSD group in the 9th week. The mRNA expression levels of inflammatory cytokines (IL-8 and TNF-α) and related pathway components (toll-like receptor 4, myeloid differentiation primary response gene 88, and nuclear factor-κB) were increased significantly in both the livers and kidneys in the HSD group. The mRNA expression levels of enzymes (adenosine deaminase, xanthine oxidase, phosphoribosyl pyrophosphate amidotransferase, and phosphoribosyl pyrophosphate synthetase 1) related to the synthesis of uric acid increased significantly in the livers in the HSD group. However, the mRNA expression level of solute carrier family 2 member 9, which plays an important role in the excretion of uric acid by the kidney, was decreased significantly in the kidneys in the HSD group. Conclusion: These results indicated that a higher SD could cause tissue inflammatory lesions in the liver and kidney and subsequently affect the metabolism and homeostasis of uric acid, and is helpful for guiding decisions related to the breeding and production of ducks.

• Journal of Plant Biotechnology
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• v.50
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• pp.19-26
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• 2023

Korean ginseng (Panax ginseng Meyer) is an economically important plant because of it is rich in saponins. It is mainly cultivated in Asia, including Korea and China. Since ginseng requires a long breeding period due to juvenility, homozygote production techniques, such as anther culture, must be urgently established. In the present study, callus induction and embryogenesis through anther culture were observed in P. ginseng. Murashige and Skoog medium was used as the basal medium suitable for callus induction. When the medium was supplemented with 3% sucrose, the callus induction rate was high and the callus size was large. Cold pretreatment did not significantly affect callus induction and embryogenesis. Embryogenesis was the most efficient when the embryo-formation medium was supplemented with 1.0 or 3.0 mg/L 2,4-dichlorophenoxyacetic acid. Cultivar significantly affected anther culture efficiency. Specifically, 'Cheongseon' showed the highest embryo-formation efficiency, whereas no embryogenesis occurred in 'Sunun'. Ploidy assessment revealed the haploid status of the induced calli. Embryos derived from anther culture formed shoots upon transfer to germination medium, although no difference in ploidy was noted between the induced callus and control. Overall, the anther culture conditions established in the present study may contribute to the production of homozygous P. ginseng plants in the future.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.131-143
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• 1999

This study was attempted to find the mutual relationship between leisure activities and life satisfaction by the aged persons in a rural area. The data was obtained by interview with questionnaire and the data from 209 persons aged over 65, residing in Dohwa-myeon and Podu-myeon, Koheung-kun, Chollanam-do were analysed. The survey was carried out from Feb. 16th to May 3rd in 1998 and the results are as follows: 1. The survey showed that the major leisure activities were TV watching followed by talking with friends, club activities, taking a walk, visiting friends' or relatives' home and breeding domestic animals. 2. The types of leisure activities were classified into 8 patterns as active self-enlightenment, passive self-enlightenment, temporal amusements, passive self-activities, cozy introspective activities, friend oriented activities, family oriented activities and religious activities. Among the above 8 patterns active self-enlightenment type contributed most to the life satisfaction. 3. The major factors affecting leisure activities were sex, age, average income, religion and educational status. And the major factors affecting life satisfaction were sex, age average income, educational status and a state of health. In conclusion the more the aged persons participated in leisure activities, the better they felt life satisfaction.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.260-279
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• 2010

The analysis on bibliography and field investigation of Callipogon relictus Semenov, 1898 (Korean natural monument number 218) shows that the size varies from country to country, and Korean specimens, for which male is 85~120mm and female is 65~85mm, are found to be the largest. The average diameter and length of egg are 2.60mm and 6.72mm respectively. The larva has milky color and is about 100~150mm in length. The pupa is nearly 70~110mm. An adult generally appears from June to September in Korea in the broadleaf forest of lowland, whereas it appears from June to July in China. It is known that the pupa largely feed on the old tree trunk of Carpinus laxiflora (Siebold & Zucc.) blume in Korea, but no such data have been reported in China and Russia, showing differences in host plants. While the larva period is not exactly known in Korea, it is reported to be two years in China. It appears that the species inhabits in very limited regions of approximately between geographical latitude $37.5^{\circ}{\sim}47.8^{\circ}$ and longitude $126^{\circ}{\sim}140^{\circ}$ including Korea, China and Russia. To conserve the long-horned beetle in Korea, this research drew out following some conclusions through analyzing the references and field survey data. First, it need to perform precise survey on the natural environment of occurring and collected area or place including host plant kinds, temperate, humidity, latitude, longitude etc. Second, habitat region must be designated as a restricted development area, and it need to exclude or reduce the damage factors to prosper reproduction of the species. Third, it is necessary to keep loosing cautiously artificial breeding individuals in the reported sites, not disturbing scope of natural populations. Fourth, it needs to educate or publicize many people importance and value of this species through many methods.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.2
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• pp.105-111
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• 1975

Nitrogen efficiency for grain yield(E) and its relation to grain yield(Y), harvesting index(HI), percent translocation of nitrogen from straw to grain(T), nitrogen uptake amount(N), concentration in grain (GN%) or straw (SN%) and total dry matter yield (TY) among rice varieties (Oryza sativa, old and new varieties) were investigated at four nitrogen nutritional status (high and low fertilizer levels in high and low fertility fields) by simple correlation analysis. Relation between any two of above parameters or total dry matter yield (TY) and nitrogen efficiency for total dry matter yield (TE) was also investigated. 1. E is significantly and positively correlated with T, Y, HI but negatively with SN%, N, GN% and in negative trend with TY. 2. T is significantly and positively with GN% or Y, but negatively with SN%. 3. TE is significantly and positively correlated with TY but negatively with N. 4. The order of E among varieties showed consistency among different nitrogen nutritional environments. 5. From the above facts it was concluded that high yielding varieties have high nitrogen efficiency due to high percent translocation of nitrogen from straw to grain, subsequent low nitrogen concentration in straw and that translocated nitrogen in grain is greatly diluted with photosynthates. 6. Reported physiological characteristics of newly bred high yielding IR lines are well accordance with their high nitrogen efficiency and rice breeding was a selection on the basis of nitrogen efficiency. 7. It is postulated that high nitrogen efficiency varieties for yields have high nitrogen efficiency for root growth in early stage so that uptake more efficient soil nitrogen in later growth stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.327-338
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• 2020

In recent years, the temperature of Korea has been rapidly increasing due to global warming. Over the past 40 years, the temperature of Korea has risen by about 1.26℃ compared to that in the early 1980s. By region, the west region of the Gangwon Province was the highest at 1.76℃ and the Jeonnam Province was the lowest at 0.96℃. As the temperature continues to rise, it is expected that the rice yield will decrease in the future using the current standard cultivation method. As a result of global warming, the periods in which rice cultivation could be possible in regions each year has increased compared those to the past, showing a wide variety from 110 days in Taebaek to 180 days in Busan and Gwangyang. In addition, the transplanting time was delayed by 3-5 days in all regions. The average annual yield of rice showed an increasing trend when we analyzed the average productivities of developed varieties for cooked rice since the 1980s, especially in the early 1990s, which showed a rapid increase in productivity. The relationship between the average temperature at the time of development and the rice yield was divided into the periods before and after 1996. The higher the average temperature, the lower the yield of the developed varieties until 1996. However, since 1996, the increase in the average temperature did not show a trend in the productivity of the developed varieties. The climate change adaptability of developed rice varieties was investigated by analyzing the results of growing crops nationwide from 1999 to 2016 and the change in the annual yields of developed varieties and recently developed varieties as basic data to investigate the growth status of the crops in the country. As a result of annual comparisons of the yields of Taebongbyeo (2000) and Ungwangbyeo (2004) developed in the early 2000s for Odaebyeo, which was developed in the 1980s, the annual yields were relatively higher in varieties in the 2000s despite the increase in temperature. The annual yields of Samgwangbyeo (2003) and Saenuribyeo (2007), which were recently developed as mid-late-type varieties, were higher than those of an earlier developed variety called Chucheongbyeo, which was developed in the 1970s. Despite the rapid increase in temperature, rice cultivation technology and variety development are well adapted to climate change. However, since the biological potential of rice could reach its limit, it is necessary to develop continuous response technology.