• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.696-703
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• 2015

We investigated the characteristics of embryonic and abnormal organ development in haploid olive flounder, Paralichthys olivaceus, by comparing egg development and histological sections in haploid and diploid individuals. After the mid-blastula transition, abnormal development was observed in haploid fish, including delayed epiboly and malformation of the germ ring and embryonic body. In haploid flounder, Kupffer’s vesicles are irregularly shaped and of variable size compared to diploids. The embryonic body of haploids was shorter and broader than that of diploids and the tail length and size were variable. Most haploid embryos failed to hatch and the few larvae that did, did not survive for more than 6 h. The histological analysis of haploid larvae revealed deformed development in diverse organs, including the eye, otic vesicles, notochord, and neural tube. These results may be related to an abnormality in the axial system of haploid larvae. This study confirmed that the abnormalities of haploid olive flounder were similar to the reported characteristics of haploid syndrome. The abnormalities are caused by delayed epiboly and involution and deformity of Kupffer’s vesicle during egg development.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.197-201
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• 2009

The food self-support rate on the basis of cereals in Korea is approximately 27%, which will threaten the national food security. The dramatic increase in population accompanied by rapid industrialization in developing countries has caused imbalances in the supply of food and energy. To cope with these global crises over food and energy supplies as well as environmental problems, it is urgently required to develop new environmentally friendly industrial crop varieties to be grown on marginal lands including desertification areas for sustainable development. Sweetpotato (Ipomoea batatas (L.) Lam.) ranks seventh in annual production among food crops in the world. Its wide adaptability on marginal lands and rich nutritional content provide a high potential for preventing malnutrition and enhancing food security in the developing countries. In addition, sweetpotato can be developed as a bioreactor to produce valuable industrial materials including bio-ethanol, functional feed and antioxidants by molecular breeding. In this respect, we focus on the molecular breeding of sweetpotato with multi-function on marginal lands. The strategies for development of environmentally friendly industrial sweetpotato will be introduced and discussed.

• 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.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.651-657
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• 1999

These experiments focused on processing low sugar fig jam having marketability by selected substitute for extracted and purified pectinesterase (PE), colorant for colour improvement, food additive to make texture better, and stabilizer for stable storage. Cherry tomato pulp as PE substitute to hydrolyze pectin substance in fig pulp into low-methoxyl pectin was most effective among used vegetables and fruits pulp. Carmacid-R among natural colorants for imprving colour, addition of 20% starch syrup as sugar substitute for texture and addition of $MULTIPHOSE^{TM}$ for red colour change control at cold storage were effective. The low sugar fig jam processed by using the above selected materials showed higher score than others (typical jam and orange PE low sugar fig jam) for colour in sensory evaluation and did no significant difference in taste, odor, texture and overall acceptability.

• Geomechanics and Engineering
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• v.19 no.2
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• pp.105-114
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• 2019

In this paper, simulation tests were conducted with similar materials to study the distribution of residual voids in longwall goaf. Short-time step loading was used to simulate the obvious deformation period in the later stage of arch breeding. Long-time constant loading was used to simulate the rheological stage of the arch forming. The results show that the irregular caving zone is the key area of old goaf for the subsidence control. The evolution process of the stress arch and fracture arch in stope can be divided into two stages: arch breeding stage and arch forming stage. In the arch breeding stage, broken rocks are initially caved and accumulated in the goaf, followed by the step deformation. Arch forming stage is the rheological deformation period of broken rocks. In addition, under the certain loads, the broken rock mass undergoes single sliding deformation and composite crushing deformation. The void of broken rock mass decreases gradually in short-time step loading stage. Under the water lubrication, a secondary sliding deformation occurs, leading to the acceleration of the broken rock mass deformation. Based on above research, the concept of equivalent height of residual voids was proposed, and whose calculation equations were developed. Finally, the conceptual model was verified by the field measurement data.

• Asian Journal of Turfgrass Science
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• v.10 no.1
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• pp.1-11
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• 1996

Fifty accessions in Zoysia species and forty-one hybrid lines were evaluated in order to detect analyze the genectic variation of Zoysiagrasses and to obtain the basic information for breeding. 1.Plant height ranged from 13 to 34.5cm, leaf length from 7 to 26cm, leaf width from 2 to 7mm, and first leaf height from 1.1 to 8.5cm 2. The correlations among plant height, leaf length and first-leaf height were high, but leaf Width was correlated only With leaf length. 3. Stolon length was varied from 10 to 108cm, number of stolons from 12 to 53, internode length from 2 to 6.1cm and coverage percentage from 10 to 90%. 4.There were correlation among stolen length, number of stolons, internode length and coverage percentage except between stolen and internode length. 5.M1J and MC2 showed the highest level in stolen length, number of stolons and coverage percentage. Therefore they will be the best breeding materials for the purpose of fast covering. 6.According to the analysis on October 26, 1995, yellow color-change rate of leaves ranged from 5 to 85%, red color-change from 0 to 75% and sum of yellow and red change from 20 to 95%. Speciallty M2M1 and FL-41 kept green color untill early December, indicating that they had the late dormancy. 7. Visual assessment of stolon length and number of stolons, showed similar tendency With actually measured data. 8. Shoot density was very high in M2M1 and S2, and showed negative correlation with leaf width. 9. It is known in Korea that the darker green color of lawngrass is, the better it looks. There were 11 lines with dark green color leaves such as J 85-10, Meyer in Z. japonira, one asacession in Z. matrella and M2M1, M2S8, JM2, 55C2 in hybrid lines.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.381-389
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• 2010

This study was carried out to develop the breeding and/or cultivation materials by investigating characteristics of natural habitats of Allium monanthum in South Korea. Natural habitats of sunny, half-shady, and shady conditions were 13 (10.7%), 66 (54.6%), and 42 (34.7%), respectively. Natural habitats were located around upland (45.4%), around Buddhist temple area (28.1%), on mountain area (18.2%), along roadside (2.5%), and along riverside (5.8%), respectively. Natural habitats ranged widely in all areas of Korea by $33^{\circ}N{\sim}38^{\circ}N$ and $126^{\circ}E{\sim}129^{\circ}E$. In Chungbuk and Gyeongbuk natural habitats were more than in Jeonbuk and Jeonnam. Distribute pattern were formed densely. Sprout stage was from September till March of next year. Grew from March to April, and there was no plant formed flower stalk in natural habitats.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8_spc
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• pp.1284-1295
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• 2019

Considerable progress in reproduction of dairy goats has been made, with advances in reproductive technology accelerating dairy goat production since the 1980s. Reproduction in goats is described as seasonal. The onset and length of the breeding season is dependent on various factors such as breed, climate, physiological stage, male effect, breeding system, and photoperiod. The reproductive physiology of goats was investigated extensively, including hypothalamic and pituitary control of the ovary related to estrus behavior and cyclicity etc. Photoperiodic treatments coupled with the male effect allow hormone-free synchronization of ovulation, but the kidding rate is still less than for hormonal treatments. Different protocols have been developed to meet the needs and expectations of producers; dairy industries are subject to growing demands for year round production. Hormonal treatments for synchronization of estrus and ovulation in combination with artificial insemination (AI) or natural mating facilitate out-of-season breeding and the grouping of the kidding period. The AI with fresh or frozen semen has been increasingly adopted in the intensive production system, this is perhaps the most powerful tool that reproductive physiologists and geneticists have provided the dairy goat industry with for improving reproductive efficiency, genetic progress and genetic materials transportation. One of the most exciting developments in the reproduction of dairy animals is embryo transfer (ET), the so-called second generation reproductive biotechnology following AI. Multiple ovulation and ET (MOET) program in dairy goats combining with estrus synchronization (ES) and AI significantly increase annual genetic improvement by decreasing the generation interval. Based on the advances in reproduction technologies that have been utilized through experiments and investigation, this review will focus on the application of these technologies and how they can be used to promote the dairy goat research and industry development in the future.

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.313-320
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• 2018

Rice is the staple food of more than 50% of the world population. Cultivated rice has the AA genome (diploid, 2n = 24) and small genome size of only 430 megabase (haploid genome). As the sequencing of rice genome was completed by the International Rice Genome Sequencing Project (IRGSP), many researchers in the world have been working to explore the gene function on rice genome. Insertional mutagenesis has been a powerful strategy for assessing gene function. In maize, well characterized transposable elements have traditionally been used to clone genes for which only phenotypic information is available. In rice endogenous mobile elements such as MITE and Tos have been used to generate gene-tagged populations. To date T-DNA and maize transposable element systems have been utilized as main insertional mutagens in rice. The Ac/Ds system offers the advantage of generating new mutants by secondary transposition from a single tagged gene. To enhance the efficiency of gene detection, advanced gene-tagging systems (i.e. activation, gene or enhancer trap) have been employed for functional genomic studies in rice. Internationally, there have been many projects to develop large scales of insertional mutagenized populations and databases of insertion sites has been established. Ultimate goals of these projects are to supply genetic materials and informations essential for functional analysis of rice genes and for breeding using agronomically important genes. In this report, we summarize the current status of Ac/Ds-mediated gene tagging systems that has been conducted by collaborative works in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.39-46
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• 1980

A male sterile facilitated recurrent selection population was developed by the barley breeding team of Yeongnam Crop Experiment Station. To breed this population, three composite cross populations and a composite population of breeding lines in our country were used as the materials. This population was developed in order to breed early maturing, wet-soil tolerant and high yielding barley varieties, adapted for double cropping with rice in southern part of Korea. The population was named by RSPYB#l which means Recurrent Selection Population No.1. of Yeongnam Barley.