• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.414-421
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• 2019

Pod shattering during the maturing stage causes a serious yield loss in soybean. It is the main limiting factor of soybean cultivation and mechanization. It is important to develop varieties suitable for mechanical harvesting and to develop energy-efficient agricultural machinery to save labor and costs. 'Daewonkong,' developed by the National Institute of Crop Science (NICS) in 1997, is an elite cultivar that occupies more than 80% of the soybean cultivation area in Korea because of its strong tolerance to pod shattering. The objectives of this study were to investigate the variation in pod shattering degree in a RIL population developed from a 'Daewonkong' parent and to select promising lines with pod shattering tolerance. 'Daewonkong' demonstrated a high level of tolerance to pod shattering compared to the 'Tawonkong' and 'Saeolkong' varieties, with no shattered pods after 72 hours of drying. Screening of pod shattering showed a clear distinction between the tolerant and susceptible varieties. Also, the distribution of shattering pod ratio in the two populations showed a similar pattern for three years. The promising lines with pod shattering tolerance included 27 lines in the 'Daewonkong'×'Tawonkong' population and 21 lines in the 'Daewonkong'×'Saeolkong' population. The promising lines are expected to be widely used as breeding parents for creating soybean cultivars with pod shattering tolerance.

• Journal of Ecology and Environment
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• v.43 no.3
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• pp.282-288
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• 2019

We investigated the changes in the population size and inter-specific space usage for breeding in mixed breeding sites of the great cormorant (Phalacrocorax carbo), grey heron (Ardea cinerea), great egret (Ardea alba modesta) and intermediate egret (Egretta intermedia) in Gammul-myeon, Goesan-gun, Chungcheongbuk-do, South Korea, in 2016-2017. These species bred in two adjacent habitats (site A and site B). The number of breeding pairs of all species and the size of the breeding area at site B increased in 2017. In 2017, great cormorants at site B occupied the breeding sites previously occupied by the other species in 2016, while the grey heron and great egret occupied the sites around the great cormorant breeding site. The heights of nest trees and nests of great cormorant and grey heron did not differ temporally, but these heights in site B were significantly higher than those in site A for great cormorants. For great egrets, these greatly decreased in site B in 2017. Thus, the great cormorant either moved to favourable nest sites for breeding success or selected nest sites used by the herons in the previous year. Further studies of these two possibilities are necessary.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.1
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• pp.25-32
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• 2019

This study was carried out to investigate the changes in fatty acid composition and phytosterol content of the autumn sowing waxy corn during its ripening period for the production of high quality and value-added fresh ears. The content of crude oil in the waxy corn kernels steadily increased with days after pollination(DAP); the crude oil content in Heukjinjuchal (HC) was higher than that in Ilmichal (IC). The composition of fatty acids according to DAP showed a statistically significant change; palmitic and linoleic acid composition gradually decreased, but oleic acid increased, and the composition of unsaturated fatty acids in HC was higher than that in IC. The phytosterol content was increased until 33 DAP, and was 937.7 mg/100g and 867.9 mg/100g in IC and HC, respectively, but there was no statistically significant difference between the varieties. The phytosterol contents in IC varied in the following order: ${\beta}-sitosterol$ > stigmasterol > campesterol, but that in HC varied in the order ${\beta}-sitosterol$ > campesterol > stigmasterol. The campesterol content did not show significant differences between the varieties, but the stigmasterol and ${\beta}-sitosterol$ content was significantly higher in HC than in IC. Palmitic, linolieic, and linolenic acid were significantly correlated with campesterol and ${\beta}-sitosterol$, and stearic acid was positively correlated with stigmasterol. Oleic acid was positively correlated with campesterol and ${\beta}-sitosterol$ but negatively correlated with stigmasterol. As a result, it was suggested that fatty acids may affect the variation in phytosterol contents during the ripening period in waxy corn.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1519-1523
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• 2005

By screening a subtracted cDNA library constructed with mRNA obtained from the longissimus dorsi muscles of F1 hybrids Landrace${\times}$Yorkshire and their Yorkshire female parents, we isolated two partial sequences coding for the H3-K4-specific methyltransferase (KIAA1717) and skeletal muscle myosin regulatory light chain (HUMMLC2B) genes. In the present work we investigated two SNPs, one (C1354T) at the 3' untranslated region (UTR) of KIAA1717 and one (A345G) at the SINE (PRE-1) element of HUMMLC2B, in a resource population derived from crossing Chinese Meishan and Large White pig. The selected pigs were genotyped by means of a PCR-RFLP protocol. Significant associations were observed for the KIAA1717 C1354T polymorphic site with thorax-waist backfat thickness (p<0.05), buttock backfat thickness (p<0.05), average backfat thickness (p<0.05), loin eye height (p<0.05), loin eye area (p<0.05), carcass length to 1$^{st}$ spondyle (p<0.01) and carcass length to 1st rib (p<0.01). HUMMLC2B A345G were significantly associated with loin eye width (p<0.05), loin eye area (p<0.05). Further studies are needed to confirm these preliminary results.

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.321-336
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• 2018

Sesame (Sesamum indicum L.) is an important oilseed crop grown in tropical and subtropical areas. The objective of this study was to investigate the genetic relationships among 129 sesame landraces and cultivars using simple sequence repeat (SSR) markers. Out of 70 SSRs, 23 were found to be informative and produced 157 alleles. The number of alleles per locus ranged from 3 - 14, whereas polymorphic information content ranged from 0.33 - 0.86. A distance-based phylogenetic analysis revealed two major and six minor clusters. The population structure analysis using a Bayesian model-based program in STRUCTURE 2.3.4 divided 129 sesame accessions into three major populations (K = 3). Based on pairwise comparison estimates, Pop1 was observed to be genetically close to Pop2 with $F_{ST}$ value of 0.15, while Pop2 and Pop3 were genetically closest with $F_{ST}$ value of 0.08. Analysis of molecular variance revealed a high percentage of variability among individuals within populations (85.84%) than among the populations (14.16%). Similarly, a high variance was observed among the individuals within the country of origins (90.45%) than between the countries of origins. The grouping of genotypes in clusters was not related to their geographic origin indicating considerable gene flow among sesame genotypes across the selected geographic regions. The SSR markers used in the present study were able to distinguish closely linked sesame genotypes, thereby showing their usefulness in assessing the potentially important source of genetic variation. These markers can be used for future sesame varietal classification, conservation, and other breeding purposes.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.369-375
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• 2009

This study was attempted to survey the prevalence of heartworm infection among 253 dogs (male 167, female 86) on the 16 breeding farms in southern Gyeongnam area in May to December 2007. The results obtained from this experiment were summarized as follows; Fifty seven (22.5%) of the 253 examined dogs were heartworms-antigen positive, while twenty five dogs were Microfilaria positive by the modified Knott's method. The regional infection rates were of 25% in Tongyeong and 21% in Goseong, and on the breeding environment aspects, infection rates were lower in rural area than urban area farms. The infection rates were higher in female (26/86, 30.2%) than male dog (31/167, 18.6%). The infection rates by breeding size of farms were 31% (11/35) at <20 head, 26%(35/135) at 20~50 head and 13% (11/82) at >50 head. The infection rates of heartworm in examined dogs at the age of <2, 2~4 and >5 were 10.7% (8/75), 26% (40/154) and 37.5% (9/24), respectively. In the microfillaria-infected 25 dogs, identified Dirofilaria immitis of 21 (84%) using PCR. The dogs infected with heartworm showed the increased number of eosinophil.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.6
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• pp.73-91
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• 2014

Recently the countries breeding bears such as China and Vietnam are promoting a policy that gives relief to wild animals through agreement with AAF and WSPA. Currently our country has lacking breeding space for the increased number of bred bears due to the prohibition of bear import and export from joining the CITES in 1992. There needs to be a place that treats, protects accepts breed bears in the terms of animal welfare. The bear park was hoped to be designed as a means to give relief to bears and promote harmony with the local society, and is made of parking area, waiting area, visitors center, treatment research management facilities, restaurants, food warehouse, food store, bear museum, sanitation facilities, gondola, plaza, rehabilitation area for wild animals, outdoor exhibition center, direct indirect experience area of wild animals, resting facilities and areas, photo zones, bear playground, bear experiencing facilities, fences, information facilities, tree protection facilities and more. The design can be used as a reference in examining alternative measures following the future change in breeding policy as a bear park example which reflected the ecology of a bear in the term of animal welfare.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.37-43
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• 2008

We analyzed soil characteristics, soil seed banks, and plant communities in a small islet in Ganwol Lake from May 2005 to August 2006 to examine the forces driving plant settlement on sand bars and the effects of plant settlement patterns on nesting sites of little terns (Sterna albifrons). The soil nutrients contents in a site where the feces of wintering birds accumulate (N: 15.4 mg/kg, P: 10.5 mg/kg, LOI: 0.51 %, pH: 6.8) and a site where organic sediments accumulate (N: 20.7 mg/kg, P: 16.4 mg/kg, LOI: 0.40%, pH: 6.6) were much higher those of a control site which was not affected by bird feces and organic sediments (N: 4.1 mg/kg, P: 5.4 mg/kg, LOI: 0.41%, pH: 6.7). However, a seed bank was formed only on the site with accumulated organic sediments. Plant settlement was accelerated by feces from wintering birds and organic sediment accumulation on sand bars in Ganwol Lake. The percentage of area disturbed by human activities increased from 0.2% in May 2005 to 13.9% in August 2006, and the percentage of annual communities increased from 27.5% to 43.3%, but the percentage of open area decreased from 55.2% to 28.0% from May 2005 to August 2006. These increases in disturbed area and annual communities decreased the open area for breeding of little terns. The enlargement of P. communis and T. angustata communities was suppressed by irregular flooding. These results provide useful information for the management of little tern breeding sites for conservation purposes.

• Ocean and Polar Research
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• v.41 no.2
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• pp.99-105
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• 2019

Black-tailed gulls, Larus crassirostris, have been known as resident birds in Korea, but their wintering and breeding habitat ranges were little known about. We investigated the habitat ranges of Blacktailed gulls breeding on Dokdo Island - which is the eastern end of their breeding colonies in Korea. Three adult Black-tailed gulls were fitted with Global Positioning System data loggers in May 2018 and their positions were tracked for 9 days, 245 days and 365 days each respectively. Black-tailed gulls stayed on Dokdo Island until June for breeding purposes and moved down to the southern part of Japan for wintering. The following year, a Black-tailed gull started to move northward in February and returned to Dokdo Island in April. They traveled a total of $207,334-229,507km^2$ (MCP) throughout a whole year. Based on location density categories accounting for 50% of locations, they used 3,618 to $3,803km^2$ in area. Black-tailed gulls breeding on Dokdo Island used smaller habitat ranges during the wintering period than the other periods. This is the first report on the habitat ranges of Black-tailed gulls breeding on Dokdo Island.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.255-260
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• 1994

Calving records of 107 heifers from two breed groups were used to identify the major factors contributing to calving difficulty (dystocia) and compare the influence of pelvic diameters, weight and height of heifers measured after breeding and before calving on dystocia. The horizontal and vertical pelvic diameters, hip height and weight of heifers were measured two months after breeding and again two months before calving. Snell transformed calving difficulty scores (0 = normal to 100 = surgical intervention) were used in analyzing the data by analysis of covariance. Body condition score of the heifer, sire birth weight of the calf, birth weight of the calf, and ratio of calf birth weight to pelvic area all had significant effects on dystocia. Calf birth weight, ratio of calf birth weight to pelvic area, and heifer's condition score were especially important. However, sex of calf did not have a significant influence on dystocia. Generally, the variables measured before calving accounted for a higher proportion of variation in dystocia than those measured after breeding. Thus, based on the relative importance of the major factors affecting dystocia, it is suggested that selection of bulls with low birth weight for breeding on normal size heifers with optimum body condition score, and well developed pelvic opening, would be effective in reducing the incidence and severity of dystocia in beef heifers.