• Journal of the Korea Organic Resources Recycling Association
• /
• v.29 no.2
• /
• pp.15-23
• /
• 2021

This study was conducted to evaluate the field application of the developed recommendation system in organic rice (Oriza sativa L.) paddy and to investigate the mineral nitrogen content in soil and rice productivity. According to the developed system, hairy vetch (HV), rye+rapeseed oil cake (R+OC), rapeseed oil cake (OC) for only basal fertilization (OC-B), OC for split application (OC-S), pig manure compost (PMC), and chemical fertilizer (CHM) were applied to paddy soil at the rate of 107~133 kg N/ha. Results were followed, unhulled rice yield of OC-S (111%), OC-B (110), R+OC (106), HV (101), and PMC (96) were no significantly different with CHM (100). Also there was positive correlation (R²=0.803^*) between unhulled rice yield and cumulative inorganic N in soil. For nitrogen use efficiency of rice, OC-B, OC-S, and R+OC were not significantly different with CHM. In conclusions, the developed organic materials use recommendation system was effective for organic rice productivity. It could be useful for organic farmer to apply the organic materials use recommendation system for rice.

• Korean Journal of Poultry Science
• /
• v.47 no.4
• /
• pp.237-245
• /
• 2020

This study investigated the effects of breed, laying age, and egg storage period on hatching performance. Eggs were collected from early laying period (27 to 29 weeks old) and late laying period (50 to 52 weeks old) in Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Eggs laid for each period were stored for 3, 7 and 14 days and then hatched. Fertility, hatchability, and embryonic mortality were observed to determine the hatching performance. The results showed that hatching performance was affected by breed, laying age, and egg storage period with independently or interactively. The Korean Rhode Island Red breed had the lowest hatching performance. Hatchability and early embryonic mortality rate increased in early laying period eggs compared to the late laying period, but the late embryonic mortality rate increased in late laying period eggs. Additionally, hatching performance decreased as the egg storage period increased. Using breed-specific hatching management techniques, avoiding late laying period eggs, and shortening the egg storage period to seven days after laying may improve the hatching performance.

• Journal of Korean Society of Forest Science
• /
• v.111 no.1
• /
• pp.100-107
• /
• 2022

Quercus mongolica is an important deciduous tree species in the Republic of Korea; it covers most of the total natural deciduous forest area in the country. In this study, the site characteristics and stand structure of Q. mongolica forests were investigated at sites where Q. mongolica occupied >50% of the total basal area during the 7th National Forest Inventory period (2016-2020). The total number of circular sample plots (400 m²) of Q. mongolica forests was 1,421. These forests were mainly dominant at >800 m above sea level (a.s.l). However, they were also distributed on north-facing slopes at <600 m a.s.l. and gradually on southern slopes with ascending altitudes. Quercus mongolica forests were distributed in silt loam, loam, or sandy loam soils with relatively high fertility. Dominant species distributed with Q. mongolica included Pinus densiflora, Quercus variabilis, Acer pseudosieboldianum, Fraxinus rhynchophylla, and Quercus serrata. Pinus densiflora and Q. variabilis grew in large DBH classes, Q. serrata grew in middle DBH classes, and A. pseudosieboldianum and F. rhynchophylla grew in small DBH classes. The dominant species distributed at the lower layer of Q. mongolica forests were Sasa borealis, Lindera obtusiloba, Rhododendron mucronulatum, Rhododendron schlippenbachii, Q. mongolica, and Fraxinus sieboldiana.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.1
• /
• pp.43-53
• /
• 2020

The test conducted in this study was carried out for three years from 2013 to 2015 to investigate the optimal level of seeding amount and nitrogen fertilizer application to cultivate and produce the seeds of rye in Jangsu province, Jeollabuk-do. The variety of forage rye used in this experiment was 'Gogu', developed by National Institute of Crop Science, Suwon, Korea in 2004. The seeding rate was four levels (3, 5, 7 and 9 kg 10a^-1, respectively) while nitrogen fertilized with respective amounts of 0, 3, 6, and 9 kg 10a^-1. In Jangsu, the number of spike per m² and lodging ratio were increasing, while fertility rate, 1 liter weight, 1000-grain weight and seed productivity were decreased by increasing of seeding rate from 3 kg 10a^-1 to 9 kg 10a^-1. There was an increase in the number of spike per m², culm lengh, the number of grain per spike, lodging ratio and seed productivity, while productiove tiller, 1 grain weight, and 1 liter weight were decreased by increasing nitrogen fertilizer level from 3kg 10a^-1 to 9 kg 10a^-1. The best seeding rate and nitrogen fertilizer level for rye seed production were 5 kg and 6 kg 10a^-1, respectively, considering plant lodging, seed and fertilizer reduction and the prevention of pollution by excess fertilization.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.5
• /
• pp.608-618
• /
• 1996

Wild perennial types of genus Glycine, as sources of genetic diversity, have been recently employed in the soybean breeding programs. This study was carried out to introduce some useful characters of wild perennial Glycine tomentella into common cultivars, G. max. Parent materials used for interspecific hybridization were three common cultivars, Ulsankong, Baemkong and Danyeobkong, and four G. tomentella strains having different diploid(2n) of 38, 40, 78, and 80. Their cross-fertility, effect of reciprocal cross, development comparison of crossing pod and optimum timing to efficient crossing were investigated. Plant were grown in 1/2,000 Wagner pots in greenhouse and field. Crossing efficiency and pod survival rate were the highest in 2n=38 of the four G. tomentella strains when the common cultivars were fixed as female parents. In the reciprocal cross of three common cultivars and four G. tomentella strains, when the former was used as maternal sources, they showed better crossing rate and longer pod survival than the latter. In the interspecific hybridization between G. max cv. Baemkong andG. tomentella, 2n=38, the pod formed from the female G. tomentella had relatively greater size and weight than that from the female Baemkong in comparison with parents. However, the reverse result was true in a number of ovules per pod. More efficient interspecific hybridization in the field was made on August 20, when temperature and relative humidity were higher and day length was shorter, than one or two months earlier.

• Korean Journal of Poultry Science
• /
• v.50 no.3
• /
• pp.119-124
• /
• 2023

This study was conducted to investigate the effect of dietary levels of the metabolic energy (ME) on performance, egg quality, and hatchability of Woorimatdag breeder hens during late laying period. A total of eighty Woorimatdag breeder hens were individually housed in cages from 48 to 64 weeks of age. The hens were assigned to two groups with different dietary ME levels: 2,500 kcal/kg and 2,700 kcal/kg. Each group consisted of four replicates of ten birds. The results indicated that the dietary ME levels did not have a significant effect on the body weight and feed intake of the breeder hens. The egg production was significantly (P<0.05) higher in breeder hens fed 2,500 kcal/kg ME than in those fed 2,700 kcal/kg ME from 48 to 52 weeks of age. However, the egg production was shown to be similar values in both groups from 52 to 64 weeks of age. No significant differences were observed between groups with respect to egg weight, eggshell thickness, and eggshell strength of breeder's eggs. There was no difference in the fertility and hatchability between dietary groups. In conclusion, 2,500 kcal/kg of dietary ME could be considered to meet Woorimatdag breeder hens requirement sufficiently during late laying period.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.6
• /
• pp.795-799
• /
• 2023

The Canadian military participated in World War I and felt the limitations of the recruitment system through the continuous shortage of troops caused by the prolonged war, therefore expanded the role and scope of female manpower. The use of female manpower, which began with medical support for the first time, increased its necessity and importance as medical support personnel were dispatched overseas and women's manpower was expanded to combat support missions for the Army, Navy, and Air Force. Since then, the proportion of female manpower has been limited to 1.5% of the total number of employees at the end of the Second World War and the reduction of troops and the dismantling of the women's unit. In this situation, the Austrian Defence Force gradually accepts the recommendation of the Royal Canadian Women's Status Committee to improve the service conditions of women, marking a turning point in expanding the role of women in the Canadian military. The the Austrian Defence Force conducted long-term combat experiments to increase the proportion and role of female manpower, increasing reliability through observation and analysis to prove whether female manpower is suitable for combat troops. Korea also wants to draw implications for the future direction by comparing the history and current appearance of the Canadian military's use of female manpower with the Korean military at a time when the problem of a shortage of troops is emerging due to the recent decline in fertility and low birth rates.

• Journal of Korean Society of Forest Science
• /
• v.113 no.2
• /
• pp.143-152
• /
• 2024

This study was conducted to evaluate the growth and nutrient dynamics in response to fertilization of four tree species (LT: Liriodendron tulipifera L.; PY: Prunus yedoensis Matsumura; QA: Quercus acutissima Ca rruth; a nd PT: Pinus thunbergii Parl.) planted in a fire-disturbed urban forest in Bongdaesan (Mt.), Ulsan Metropolitan Area, South Korea. The trees were planted in 2009, and compound fertilizers (N₆P₄K₁) were applied in April 2013 and March 2014. Tree growth, soil, and foliage nutrients were examined from March 2013 to October 2016. The regression coefficients for the increment of the diameter at breast height (DBH) significantly differed between the fertilized and unfertilized plots, suggesting the significant effects of fertilization. By contrast, fertilization did not affect the coefficients for height increments. Regarding soil nutrient contents, organic carbon and total nitrogen concentrations were lower in the fertilized plots than in the unfertilized plots, whereas available phosphorus, exchangeable calcium, and magnesium concentrations were higher in the fertilized plots than in the unfertilized plots. In foliage, nitrogen and phosphorus concentrations were higher in the fertilized plots than in the unfertilized plots, whereas potassium, calcium, and magnesium concentrations were not affected by fertilization. Nutrient concentration of foliage among the tree species were higher in LT and PY than in QA and PT. These results suggest that fertilizers may be used to enhance soil fertility and the growth and nutrient status of tree species planted in a fire-disturbed urban forest.

• Radiation Oncology Journal
• /
• v.14 no.3
• /
• pp.221-228
• /
• 1996

Purpose : We tried to evaluate the clinical characteristics, the treatment methods, the results of treatments, and the Patterns of failure in ovarian dysgerminoma retrospectively According to the results we would like to suggest the proper management guideline of stage la ovarian dysgerminoma patients who want to maintain fertility. Materials and Methods : Between 1975 and 1990, 34 patients with ovarian dysgerminoma were treated at the Yonsei University Hospital. The case records of these patients have been reviewed for presenting symptoms, treatment methods, local control and survival following treatment. Excluded from analysis were five patients with mixed ovarian germ cell tumors and gonadoblastomas (46,XY) Treatment results of the twenty nine patients were analysed by each treatment modality. Twenty one patients were treated with surgery and postoperative adjuvant radiotherapy (group 2). The other eight patients were treated with operation alone (group 2). The median age of twenty-nine patients was 23 years with a range of 8 to 39 years. Presenting symptoms were abdominal mass (20) pelvic discomfort or pain (5) et al. Radiotherapy was performed by 10MV LINAC or Co-60 teletherapy unit. The total radiation dose of the whole abdomen was 20-25 Gy/3weeks, 1-1.5 Gy/fraction with a boost to the whole pelvis 10-15 Gy/l-2weeks 1.8-2.0 Gy/fraction. Advanced stage disease (stage II or stage III) patients received prophylactic mediastinal and supraclavicular irradiation to a dose of 16-26 Gy. Median duration of follow-up of living patients was 80 months (range 13-201 months). Results : All of the twenty one patients of group 1 were alive without disease ($100\%$). Among the eight patients who were not treated with radiotherapy (group 2), six patients developed local recurrence. Four Patients referred with recurrent disease were treated with salvage radiotherapy. Three of four patients were salvaged and one Patient who had recurrent intra-abdominal disease died of progressed carcinomatosis at 11 months after salvage radiotherapy. The other two patients with recurrence were salvaged with chemotherapy (1 patient) or re-operation (1 Patient). Twenty eight patients remained alive without disease at last follow up, so the 5 year local control rate and 5 year overall survival rate for all groups were $96.6\%$ (28/29), respectively. Among thirteen patients with stage la unilateral tumors seven patients were treated with postoperative radiotherapy and the other six patients were treated with unilateral salpingo-oophorectomy alone. Five patients who did not received radiotherapy developed local failure but all of the recurrent ovarian dysgerminomas were salvaged with radiotherapy, chemotherapy or re-operation. So all the 13 patients with stage la ovarian dysgerminoma were free of disease from 20-201 months (median 80 months). Conclusion : The authors consider external irradiation to be an effective treatment as a complement to surgery in ovarian dysgerminoma. For those patients with disease presenting in stage la tumors who wish to maintain fertility, unilateral salpingo-oophorectomy alone may be curative and spare ovarian function considering excellent salvage rate of recurrent ovarian dysgerminoma in present study.

• Korean Journal of Poultry Science
• /
• v.17 no.3
• /
• pp.179-191
• /
• 1990

In order to study the effects of supplementation of live yeast(Saccharomyces cerevisiae) on the performance of laying hens, five experiments were conducted. Two experiment were conducted during summer period, one with 37 wk old Dekalb-Delta strain laying birds(Exp. 1) and the other one with 100 wk old molted Nick Chick Brown laying birds(Esp.2) . In each experiment, 240 birds were divided into 12 groups of 20 birds each and randomly distributed. Each of the two experimental diets(Control 71 and 0.05% live yeast supplemented 72) was fed to 6 groups for 4 wks in Exp.1 and 3 wks in Exp.2. Three experiments were conducted during winter period, Exp.2 with 54 wk old Hy-Line strain laying birds, Exp.4 with 52 wk old Hy-Line strain laying birds, and Exp.5 with 36 wk old broiler breeder(Indian River strain). In each experiment, 540 birds were divided into 18 groups of 30 birds each and randomly distributed. Each of the 3 experimental diets(Control：$T_1$0.05% live yeast supplemented：$T_2$ and 0.1% live yeast supplemented ： T$_3$) was fed to 9 groups for 6 wks in Exp.3, 9 wks in Exp.4 and 4 wks in Exp.5. In Exp.4, Latin Square design was employed to determine the effects of switching feeds at 3 wk intervals. All hens were housed in cages of commercial farm and experimental diets were made with commercial layer feeds. In Experiment 1, egg production was significantly(P＜0.05) higher in $T_2$. Feed intake was significantly (P＜higher in 72 at 1st wk but 4 wk average was not significantly different. Feed efficiency was significantly(P＜0.01) better in 72 at End wk but 4 wk average was not significantly different. Other parameters, such as weight, soft egg production, cracked egg production and mortality were not significantly different. In Experiment 2, egg production was significantly(P＜0.05) higher in $T_2$. Feed efficiency was significantly (P＜0.05 and P＜0.01) better at End wk and 3rd wk but 3 wk average was not significantly different. Soft egg production was significantly(P＜0.05) higher in 72. Other parameters were not significantly different. In Experiment 3, egg productions were significantly(P＜0.05) different among treatments ： $T_3$ was higher than $T_1$ and $T_2$ was higher than $T_1$. Egg weight of $T_1$ and $T_2$was significantly(P＜0.05) heavier than $T_3$. Feed intake of $T_2$ and $T_3$ was significantly(P＜0.05) higher than $T_1$ at 6th wk but overall average was not significantly different. Soft egg production were significantly(P＜0.01) different among treatments：$T_1$ was higher than $T_3$ was higher than $T_2$. Feed efficiency cracked e99 Production and mortality were not signifcantly different. In Experiment 4, egg production tended to increase as the level of live yeast supplementation increased but they were not statistically different. In Experiment 5, egg production of broiler breeders of $T_3$ was significantly(P＜0.01) higher than $T_1$. Feed intake of $T_3$ was significantly(P＜0.05) greater than $T_1$ and $T_2$ at 3rd wk but overall average was not significantly different. Fertility and hatchability tended to be higher in the supplemented groups than in the control.