• Korean Journal of Plant Tissue Culture
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• v.24 no.4
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• pp.239-256
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• 1997

Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.143-148
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• 2015

A new Dianthus cultivar 'URI 2010-6' was selected among F1 progenies from a cross between interspecific hybrid 'Evergreen Emerald' as the seed parent and D. chinensis ' Ruby' as the pollen parent. In 2007, the cross w as made, and the seedlings of $F_1$ progenies were obtained and investigated. After three rounds of characteristic evaluation from 2008 to 2010, a clone was selected and registered as 'URI 2010-6' at the Korea Seed and Variety Service (plant variety protection number: 4431) in 2011. The flower of 'URI 2010-6' is caryophyllaceous, single type, and mainly bright red (Red, N79C) with secondary white (White, N155C) on the edge or as spots on the petal. The flower has diameter of 2.7 cm and length of 0.8 cm. This cultivar blooms continuously about 150 d on average and may be used as evergreen plant during winter months.

• The Korean Journal of Food And Nutrition
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• v.34 no.4
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• pp.407-414
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• 2021

This study investigated on the chemical components, quality characteristics, antioxidant compounds, and activity of maize hybrids according to the cultivar, and breeding maize seeds crossed with seed and pollen parent. The moisture, crude fat, crude ash, crude protein, carbohydrate, and amylose contents of maize hybrids were significantly different among cultivars, and seeded and pollinated maize. The L-, a- and b-value of maize hybrids were 39.81~47.21, -0.01~0.55 and 5.85~18.47, respectively. Water binding capacity, water solubility index and swelling power were 123.29~153.32, 4.69~5.76 and 20.11~21.47%, respectively. The phenolic compounds and radical scavenging activity of maize hybrids were significantly different among cultivars, and seeded and pollinated maize. Total polyphenol and flavonoid contents of maize hybrids were 1,335.41~1,876.29 ㎍/g and 184.24~453.95 ㎍ CE/g, respectively. The DPPH and ABTS radical scavenging activities were 171.75~239.16 and 299.44~364.09 mg TE/100 g, respectively. As a result, it could be used as a basic data for cultivating phenol compounds and antioxidant activity in maize breeding.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.618-626
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• 2010

Matroclinal inheritance of morphological characters in interspecific crosses of Rosa spp. can be influenced by cytoplasmic inheritance, apomixis, and asynaptic heterogamy. In asynaptic heterogamy, which is often observed from interspecific crosses of Rosa sect. $Caninae$, the polyploidy of the seed parent (especially for 5x=35) is recovered in the progeny through the pollens that include only a set of bivalents (x=7) and egg cells that contain a set of bivalents (x=7) and other univalents (3x=21). In this study, we investigated the causes of matroclinal offsprings observed from reciprocal crosses of tetraploid cut rose cultivars ($Rosa$ $hybrida$ L.) by analyzing EST-SSR marker distribution in the progeny populations. From EST-SSR marker analysis of eight offsprings per six reciprocal crosses among six cultivars, cases of cytoplasmic inheritance were not observed. Apomixis was also very rare as compared to the reports on interspecific crosses of sect. $Caninae$; only one apomitic plant was identified from the cross 'Redtem' ${\times}$ 'Red Sandra'. Although a clear-cut pattern of asynaptic heterogamy was not found, cultivar-specific marker transmission skewed to seed parent in four cultivars implied that genetic inheritance can be highly influenced by the seed parent depending on crosses among cut rose cultivars; especially, 10 out of 11 alleles specific to 'Yellow King' distributed in progenies at higher ratios when the cultivars were crossed as the seed parent.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.203-208
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• 2012

Pyeongangok, a new single cross variety, is an yellow dent maize hybrid (Zea mays L.) developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2011. This hybrid, which has a high yield of grain and dry matter, was produced by crossing two inbred lines, KS160 and KS155. KS160 is the seed parent and KS155 is the pollen parent of Pyeongangok. Silking date of Pyeongangok is 2 days earlier than that of check hybrid, Jangdaok, and equal to that of another check hybrid, Kwangpyeongok. Plant height of Pyeongangok is longer than that of Jangdaok and similar to that of Kwangpyeongok. Ear numbers per 100 plants of Pyeongangok is more than that of Jangdaok. Ear length of Pyeongangok is shorter than that of Jangdaok. 100 seeds weight of Pyeongangok is lighter than that of Jangdaok. Ear rate of Pyeongangok is lower than that of Kwangpyeongok. Stay-green of Pyeonganok is not greatly different with that of Kwangpyeongok. It has moderately resistance to southern corn leaf blight (Bipolaris maydis), black streaked dwarf virus (BSDV) and corn borer. It has strong resistance to northern corn leaf blight (Exserohilum turcicum). It has resistance to lodging. Pyeongangok was evaluated for the yields of grain and dry matter at four locations from 2009 to 2011. The yield of Pyeongangok in grain was 7.66 ton/ha. The yield of Pyeongangok in dry matter was 19.80 ton/ha. The yield of Pyeongangok in total digestible nutrient (TDN) was 13.32 ton/ha. Seed production of Pyeongangok has gone well due to a good match during crossing between the seed parent, KS160, and the pollen parent, KS155, in Yeongwol.

• Journal of Life Science
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• v.34 no.5
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• pp.313-319
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• 2024

Cultivars or genetic resources with a black seed coat and green cotyledons are rich in lutein, which can promote eye health, and anthocyanin, known for its numerous health benefits. However, mature seeds also contain P34, 7S α' subunit, and lectin proteins, which are allergenic and degrade quality. Here, we report the breeding of a new soybean line with a black seed coat, green cotyledon, and free of P34, 7S α' subunit, and lectin proteins. A total of 157 F₂ seeds with black seed coats and green cotyledons were selected by crossing a female parent with a brown seed coat, green cotyledon, and lacking the 7S α' subunit and lectin proteins with a male parent with a black seed coat, green cotyledon, and lacking the P34 and lectin proteins. The P34 and 7S α' subunit proteins were consistent with a ratio of 9:3:3:1, indicating that they are independent of each other. From 14 F₂ seeds that were recessive (cgy1cgy1p34p34) for both proteins, one individual F₂ plant (F₃ seeds) with the desired traits-black seed coat, green cotyledon, and lacking P34, 7S α' subunit, and lectin proteins- was finally selected. The triple null genotype (absence for P34, 7S α' subunit, and lectin proteins) was confirmed in random F₃ seeds. The selected line has a black seed coat and green cotyledons, and when sown on June 14 in the greenhouse, the maturity date was approximately October 3, the height was about 68 cm, and the 100-seed weight was about 26.5 g.

• Journal of Life Science
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• v.10 no.4
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• pp.317-325
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• 2000

A six parent dialled analysis was conducted to get basic information for improving yield of upland cotton. Heterosis, combining ability, genetic components and correlation coefficients for boll length, boll width, boll weight, 100 seed weight, lint weigth per boll and lint percentage were studied. Estimates of heterosis for all characters and heterobeltiosis for boll weight and lint weight per boll showed positive values. In general combining ability effect, 'Muan' and 'Imsung' showed highely positive effect in all characters. In specific combining ability effect, the combinations of 'Seungju${\times}$Imsung$.$Seosan${\times}$Imsung' for bll length, 'Cheju${\times}$Imsung$.$Seung${\times}$Imsung' for boll width, 'Cheju${\times}$Muan$.$Cheju${\times}$Imsung' for boll weight, 'Cheju${\times}$Soonchun$.$Muan${\times}$Imsung' for 100 seed weight, 'Soonchun${\times}$Muan' for lint weight per boll and 'Soonchun${\times}$Seosan$.$Seungju${\times}$Muan' for lint percentage showed highly positive effect. Partial dominance was observed for boll length, boll weight, 100 seed weight and lint weight per boll, complete dominance for boll width and overdominance for lint percentage. The number of effective gene group was estimated as one for all characters. The estimates of narrow and broad sense heritabilities were high for all characters except as one for all characters. The estimates of narrow and broad sense heritabilities were high for all characters except lint percentage. Correlation coefficients among the boll length, boll width, boll weight, 100 seed weight and lint weight per boll were positive, whereas lint percentage was negatively correlated with other characters.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.250-256
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• 1992

This study was carried out to obtain basic genetic informations in pea(Pisum sativum L.). A series of field experiments were carried out with seven pea cultivars and F$_1$ hybrids for three years. Based on the information collected from a set of diallel crosses, the behaviours of inheritance of seed yield and ten major agronomical characters were observed by the estimation of heterosis and combining ability. Heterosis for seed yield per plant was 79% and those for yield components such as number of seeds per plant, number of pods per plant, stem length, stem diameter, number of branches per plant, also showed relatively high values. General combining ability(GCA) and specific combining ability(SCA) were significantly different among major agronomic characters, and the variances of GCA were higher than those of SCA latter. Among the tested cultivars, Alderman was found to be the most promising parent based upon the GCA effects on the seed yield and yield components. The crosses of Sugar Ann$\times$Alderman, Wando$\times$Alderman and JI 1198$\times$Chinju ＃6, showed the highest SCA effects on seed yield and yield components.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.619-625
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• 2012

This study was conducted to investigate the variation of fruit, seed and germination characteristics among populations of Serrateleaf Pearlbush (Exochorda serratifolia S. Moore) distributed in Korea. Fruits collected from 96 trees in five natural populations and their five fruit, seven seed and three germination characteristics were analyzed. In 14 characteristics except for mean germination time, there were significant differences among populations and among individuals within population. Generally, fruit and seed characteristics showed higher values among population in total variance component. Coefficients of variations in weight of fruit (27.0%), length/thickness of seed (28.1%) and germination rate (52.5%) were relatively high compared to other traits. In seed germination behaviors, germination percentage, mean germination time and germination rate showed 62.9%, 64.0 days and 0.40 ea./day, respectively. As a result of simple correlation analysis, mean germination time showed a significant positive correlation with seed thickness, germination rate showed a significant positive correlation with height of parent tree and latitude, respectively. Also, latitude showed a positive correlation with fruit weight. The populations close geographically did not show the tendency of clustering into the same group. The results of principal component analysis showed that the first for principal components (PC's) explained 63.0% of the total variation. Primary 3 principal components appeared to be major variables because of the loading contribution of 97.0%.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.118-123
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• 2008

For effective production of interspecific hybrids of Lilium and valuable new cultivars, we used Lilium Asiatic hybrid 'Tiny Ghost' as the female parent, and Oriental group, and Longiflorum group and Martagon as the male parents. Percentage pollen germination in Oriental hybrid 'Sorbonne' was the highest with 64%. As results of using normal style pollination and cut style pollination methods, all seed sets were formed in normal style pollinated treatment, except in 'Aktiva'. Pollen germination percent of Longiflorum hybrid 'Norina' was higher than that 'Gelria'. However, all crossings using 'Norina' failed to set seeds. Corresponding fertilization ratio was different from genetic compatibility, even in the same group. From the crossing using 'Aktiva' as the male parent one bulb was obtained derived from one embryo sac. And using 'Sorbonne' as the male parent, one plantlet was obtained after four ovule cultures. Crossing using 'Gelria' as the male parent five embryos, 15 embryo sacs, and seven ovules per one ovary were obtained. Among them, 18 plantlets germinated, with the germination percent of 66.7%. Crossings using L. hansonii, Martagon group, as the male parent resulted in 40% germination from five ovules.