• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.180-186
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• 1994

Lipoxygenase activity of soybean seeds of approximately 507 genotypes as well as its inheritance and selection efficiency in early breeding generation was measured in the Department of Agronomy, Seoul National University to facilitate breeding for low lipoxygenase activity of soybean. Average seed lipoxygenase activity of 507 cultivars and strains was 350 unit (unit: $\Delta$0.01 /min. /mg at 234nm) and ranged from 50 to 670 unit. There was no difference in mean lipoxygenase activity according to apparent seed characters such as seed coat and embryo color. But early mature soybean genotypes had fairly low lipoxygenase activity. Lipoxygenase activity was inherited quantitatively, in which additive effect was greater than dominant one and proportion of gene with positive effects was similar to that with negative ones. Estimated narrow- and broad-sense heritabilities were 0.78 and 0.86 for lipoxygenase activity, respectively. Heritability measured from selection in early breeding lines for high or low lipoxygenase activity was 64~76% or 54~62%, respectively. And selection for high lipoxygenase activity increased by 29.7~44.7%, whereas that for low ones decreased by 21.8~27.3%, respectively, when compared to random population. Clear effect in selecting of lipoxygenase activity was present in early generation.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.428-434
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• 1997

The effect of genetic diversity in sub-populations on breeding efficiency was examined with prospect of potential crossbreeding. Simulation study of selection was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systemes; single population scheme and two population scheme. The different genetic levels were assumed to be caused by different gene frequencies. Phenotypes of two traits generated polygenic effect with additive 36 loci and residuals distributed normally were selected by selection index procedure. High genetic gain with less inbreeding was clearly recognized in the single population scheme, independently of difference in genetic level, economic weight and genetic correlation. Genetic correlation after selection in the single population scheme was lower than the two population scheme. When crossbreeding between the sub-population was taken into account, superiority of the two population scheme was suggested under those restrictions; difference in genetic level is moderate, selection criterion for the two traits is not far from even economic weight, and genetic correlation is positive with low to moderate value. The use of complementarity increased the possibility of the two population scheme.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.149-164
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• 2017

Next generation sequencing (NGS) technologies have led to the rapid accumulation of genome sequences through whole-genome sequencing and re-sequencing of crop species. Genomic resources provide the opportunity for a new revolution in plant breeding by facilitating the dissection of complex traits. Among vegetable crops, reference genomes have been sequenced and assembled for several species in the Solanaceae and Cucurbitaceae families, including tomato, pepper, cucumber, watermelon, and melon. These reference genomes have been leveraged for re-sequencing of diverse germplasm collections to explore genome-wide sequence variations, especially single nucleotide polymorphisms (SNPs). The use of genome-wide SNPs and high-throughput genotyping methods has led to the development of new strategies for dissecting complex quantitative traits, such as genome-wide association study (GWAS). In addition, the use of multi-parent populations, including nested association mapping (NAM) and multiparent advanced generation intercross (MAGIC) populations, has helped increase the accuracy of quantitative trait loci (QTL) detection. Consequently, a number of QTL have been discovered for agronomically important traits, such as disease resistance and fruit traits, with high mapping resolution. The molecular markers for these QTL represent a useful resource for enhancing selection efficiency via marker-assisted selection (MAS) in vegetable breeding programs. In this review, we discuss current genomic resources and marker-trait association analysis to facilitate genome-assisted breeding in vegetable species in the Solanaceae and Cucurbitaceae families.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.767-771
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• 2002

Breeding efficiencies were compared among three population schemes: a single population, a population with two subpopulations and a population with three sub-populations. A simulation experiment of selection was carried out for 10 generations with 20 replications each by comparing average breeding values and inbreeding coefficients among the three population schemes. Phenotypes of three traits were generated with a model comprising 36 loci, each with additive genetic effects and residuals distributed normally. Among the three population schemes, the single population scheme was definitely superior to the other two with regards to selection response and inbreeding. The multiple sub-population scheme was, however, considered to be an alternative population scheme when the difference in economic weights of the traits was small among the sub-populations, assuming moderate inbreeding depression for traits and crossbreeding. The scheme with two sub-populations had a higher genetic value than that with three subpopulations; however, the genetic values of the schemes were comparable when maternal heterosis was taken into account. The choice of population schemes may depend on the cost-sharing policy between the breeding population and the commercial population rather than just the breeding efficiency.

• Journal of Environmental Science International
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• v.30 no.2
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• pp.191-194
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• 2021

This study aimed to provide information and data for the management of insect breeding farms by identifying the appropriate density when rearing Protaetia brevitarsis larvae. The breeding box of the insects was filled with 2 L of fermented sawdust on a 50 × 35 × 15 cm sheet of plastic, and the density of the treatments was 200, 300 and 400 P. brevitarsis in the first, second, and third larval stages. Each treatment was repeated five times, and the sawdust medium was replaced three times (10 intervals). The experiments were conducted for a total of 30 days from March 1, 2020. Overall, 200 P.brevitarsis in the first, second, and third larval stages reared in the breeding box had a higher average survival rate and lower average mortality rate, thereby contributing to efficient production. In conclusion, this result suggests a way to increase production efficiency through the environmental management of insect breeding farms.

• Journal of Environmental Science International
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• v.30 no.3
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• pp.289-293
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• 2021

This study was conducted to investigate the distribution of duck production in duck housing as a function of the breeding period. The items in duck production distribution included body weight, feed intake, feed conversion ratio, and average duck production. All data were based on eight cycles (June and December, 2017; February, June, August, September, and November, 2018; February, 2019) at Farm Site 1 through 7. The most optimal results in the duck production distribution were observed at Site 1 for weight gain, feed intake, and feed efficiency. This could be explained by the fact that Site 1 was well managed in environmental improvement and sustainability. Based on these data, selective alternatives to improve duck production in duck farms are recommended as follows: first, proper management and recording of litter used as a flooring material are required, and second, continuous management such as temperature, relative humidity and ventilation is needed. Lastly, it is necessary to change duck facilities by introducing environmental management techniques. Furthermore, efforts to improve the overall facilities and management of duck breeding farms through additional field studies are needed in the future.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.298-311
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• 2015

Grape is one of the important fruit crops around the world, and exposed to disease and pests, and internal or environmental stresses in the vineyards. Breeding and cultivation of new varieties of high quality-grapes resistant to diseases and pests and tolerant to stresses are the most important steps in the grape production. However, conventional breeding has laborious and time-consuming procedures in maintaining and selecting seedlings in the fields. Development of molecular breeding technology through understanding of molecular mechanism of useful traits can be used as an alternative strategy to improve the efficiency of grape breeding program by cross hybridization in grape development programs. The completion of the grape genome sequencing project provided the way to discover the novel genes and to analyze their functions. Comparative genomics, transcriptomic analysis, and the genome-wide identification and analysis of useful genes as well as development of molecular marker for valuable traits could provide novel insights into fruit quality and the responses to diseases and stresses, and can be used as important information in molecular breeding programs for grape development.

• Korean Journal of Medicinal Crop Science
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• v.28 no.1
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• pp.21-28
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• 2020

Background: Owing to its high efficiency in lipid and protein production, peanut (Arachis hypogaea L.) is considered one of most important crops world-wide. The kernels of peanuts are undoubtedly the most important product this plant, whereas the skin is almost completely neglected in nutraceutical terms. However, peanut skin contains potentially health-promoting phenolics and dietary fiber, and there is considerable potential for commercial exploitation. In this study, we evaluated the α-glucosidase inhibitory activity of an extract of peanut skin (PS). Methods and Results: The α-glucosidase inhibitory effects of 80% ethanol extracts of peanut (A. hypogaea L. 'Sinpalkwang') skin were evaluated and found to have a half-maximal inhibitory concentration (IC₅₀) value of 1.2 ㎍/㎖. Progress curves for enzyme reactions were recorded spectrophotometrically, and the inhibition kinetics revealed time-dependent inhibition with enzyme isomerization. Furthermore, using ultra-high performance liquid chromatography combined with quadrupole-orbitrap mass spectrometry, we identified 26 compounds in the peanut skin extract, namely, catechin, epicatechin, and 24 proanthocyanidins. Conclusions: The results suggest that peanut skin can be utilized as an effective source of α-glucosidase inhibition in functional foods and nutraceuticals.

• Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.191-195
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• 2007

The aim of this study was to assess whether size-rank at the juvenile stage is associated with growth performance and sex ratio in olive flounder (Paralichthys olivaceus). Juveniles (mean body weight, $8.8{\pm}0.9\;g$) were selected from two age groups, with the high size-rank group (HSRG) fish in the upper 19.3-67.3% of 104 days post-hatching (dph) age group and the low size-rank group (LSRG) fish in the lower 9.0-55.7% of 116 dph age group. Triplicate groups of 100 fish were reared over 32 weeks. A heavier final body weight was observed in the HSRG ($360{\pm}12\;g$) compared to the LSRG ($315{\pm}9\;g$, P<0.05), whereas no differences in feed intake, feeding efficiency, and mortality were seen between the experimental groups. The percentage of females was significantly higher in the HSRG (51.7%) than in the LSRG (30.8%, P<0.05). In addition, a remarkable increase in growth was recorded in females, indicating that the relative frequency of females increased with a body weight increase. The results suggest that high size-rank juvenile olive flounder have better growth performance and a higher percentage of females, because females start growing faster than males before size grading occurs.

• Animal Bioscience
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• v.35 no.5
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• pp.670-676
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• 2022

Objective: This study was conducted to examine influence of skimmed milk-based extender (SM), INRA 96 extender and BotuSemen Gold extender on parameters of stallions' ejaculate during storage. Methods: In this study, 14 stallions between 4 and 20 years of age were monitored. Total and progressive motility, viability and morphology of sperm were evaluated at time intervals of 24, 48, and 72 hours after collection. Results: The total motility, progressive motility, and values of sperm with normal morphology were significantly higher in the INRA 96 and BotuSemen Gold extenders than in the SM (p<0.01). The sperm viability differed significantly in all extenders (p<0.01). The highest value of sperm viability was in INRA 96 (64.69%±0.67%) and lowest in SM (59.70%±0.81%). The highest differences occurred at 72 hours of storage. Values of total motility, progressive motility and sperm viability decreased over time (p<0.01). In case of sperm morphology there was no statistically significant decrease between 48- and 72-hour time intervals. Conclusion: It can be concluded that the extenders with a chemically defined composition have shown better indicators of insemination capabilities in ejaculates than the SM. The BotuSemen Gold extender is a suitable alternative to the INRA 96, when used within 48 hours; after 72 hours of storage, however, the INRA 96 showed a higher share of viable spermatozoa.