• Current Research on Agriculture and Life Sciences
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• 제31권2호
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• pp.75-82
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• 2013

Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.68-68
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• 2018

A total of 47 core collections of pepper (Capsicum chinense Jacq.) conserved in National Agrobiodiversity Center (NAC) were studied under field condition at Jeonju. All accessions were characterized for their 14 qualitative and 16 quantitative characters. Results revealed that both qualitative and quantitative characters exhibited wide variation among the studied germplasm. Distribution of fruit characters (fruit length, width, and fruit wall thickness) among the accessions was positively skewed. Of the 47 accessions evaluated, 38.3% accessions had conical shaped fruits and mature fruit color was predominantly red (51.1%), orange (21.3%) and yellow (14.9%). Principal component analyses revealed that (i) 56.64% of the qualitative (fruit shape, color and fruit surface) variation and (ii) 89.42% of the quantitative (plant width, height and fruit maturity days) variation were explained by the first two components. Clustering revealed two groups and dendrogram revealed morphological variation among accessions. The phenotypic diversity exists in this core collections provide valuable information to improve agronomic traits in pepper breeding program.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.143-143
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• 2017

Wheat is one of the most important crops in production and consumption. Despite increasing of importance, the self-sufficiency of wheat is less than 2% in Korea. To improve yield potential and broaden the genetic pool of common wheat in Korea, introduction of alien germplasms into the Korean wheat breeding program is suggested. For effective utilization of the germplasm, we introduced total 1,195 germplasms from the world, which were provided by National Plant Germplasm System (NPGS, USDA) and evaluated the yield, field performances and agronomic traits for 8 years. Among 55 countries, germplasms from Canada, Ethiopia, Mexico and United States accounts for 78%, especially germplasms collected from United States accounts for 50%. Yield comparison of germplasms and collected region analysis indicate that the high yielding germplasms are collected from countries or states of particular range of latitude. The combination analysis of the yield and agronomic traits and the geographical information of collected region will be utilized for improving Korean wheat breeding programs.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.276-276
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• 2022

Wheat is one of the most widely grown food crops worldwide. Extreme precipitation and wind disturbances increased due to the abnormal climate, which resulted in increased lodging. Introduction of dwarf genes in wheat significantly increased lodging resistance and productivity in wheat breeding. In this study, we performed the genotyping of dwarfing genes between 'Keumkang' and 'Komac 5' ('Keumkang' mutant). In addition, we investigated the relationship between plant height and several phenotypic characters using F₂ segregation populations derived from crosses between the two varieties. There was no significant difference in phenotypic characters between the two varieties except for plant height. In the genotyping analysis using dwarfing genes, mutations of two dwarfing gene were found to be induced between the two varieties. The four genotypes of the F₂ populations from a crossing between 'Keumkang' and 'Komac 5' were used to compare and evaluate the effects of two dwarfing genes. Plants with two single mutant dwarfing gene and double mutant dwarfing gene revealed reduced plant heights than control plants by 4.5%, 6.9%, and 33.2%, respectively. The phenotype analysis showed that double mutant dwarfing gene affected wheat stem growth as the length decreases from the second node, resulting in decreased plant height. However, there were no significant differences in the agronomic traits between mutant plants and control plant. These results may provide novel information about the effect of double mutant dwarfing gene on plant height, and may help improve lodging tolerance and wheat yield.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.339-339
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• 2017

The long grain rice varieties adaptable to South-east Asia tropical regions were tried to develop in Cambodian Agriculture Research and Development Institute (CARDI), Cambodia. The final goal is to develop rice varieties which can culture in diverse environmental conditions of tropical regions of South-east Asia under climate change. We collected and evaluated for agronomic traits of 131 rice germplasm from Cambodia, China, India, Indonesia, Myanmar, Philippines and Vietnam in CARDI. We selected core germplasm including leading varieties of target countries and made 813 F1 cross combinations between leading varieties of each country and promising germplasm of high yield potential, resistance to biotic/abiotic stresses, aromatic rice, and so on. Out of 607 F1s evaluated to heading date, plant type, agronomic traits, and grain type, 106 F1s selected and advanced to F2 populations. 106 F2 populations were evaluated to major agronomic traits, grain type and yield-component traits, and selected 2,560 plants in 62 F2 populations. During six seasons in 2014~2016, the lines of F3 subsequent-generation were cultured a total of 6,256 lines. In yield trial for promising lines in F5 generation, the growth duration from sowing to harvesting was 97~114 days. These lines were 88~129 in number of grain per panicle, an average of 84.6% in the range of 79.3~91.9% in the percentage of ripened grain and 17.5~22.8g in 1000-brown rice weight. The rough rice yields were in the range of 4.33~6.06 ton/ha with an average of 5.23 ton/ha. The yield was increased to 5~47% than Chulsa and 12~41% than IR66. Five lines, KR54-28-1, KR55-14-2, KR57-5-2, KR67-57-2 and KR128-19-1 were 5.33~6.06 ton/ha in rough rice yield. These high yield potential lines would be evaluated to adaptability in Cambodia, Laos, Myanmar and Vietnam during 2017.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.155-155
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• 2017

The long grain rice varieties adaptable to South-east Asia tropical regions were tried to develop in Cambodian Agriculture Research and Development Institute (CARDI), Cambodia. The final goal is to develop rice varieties which can culture in diverse environmental conditions of tropical regions of South-east Asia under climate change. We collected and evaluated for agronomic traits of 131 rice germplasm from Cambodia, China, India, Indonesia, Myanmar, Philippines and Vietnam in CARDI. We selected core germplasm including leading varieties of target countries and made 813 F1 cross combinations between leading varieties of each country and promising germplasm of high yield potential, resistance to biotic/abiotic stresses, aromatic rice, and so on. Out of 607 F1s evaluated to heading date, plant type, agronomic traits, and grain type, 106 F1s selected and advanced to F2 populations. 106 F2 populations were evaluated to major agronomic traits, grain type and yield-component traits, and selected 2,560 plants in 62 F2 populations. During six seasons in 2014~2016, the lines of F3 subsequent-generation were cultured a total of 6,256 lines. In yield trial for promising lines in F5 generation, the growth duration from sowing to harvesting was 97~114 days. These lines were 88~129 in number of grain per panicle, an average of 84.6% in the range of 79.3~91.9% in the percentage of ripened grain and 17.5~22.8g in 1000-brown rice weight. The rough rice yields were in the range of 4.33~6.06 ton/ha with an average of 5.23 ton/ha. The yield was increased to 5~47% than Chulsa and 12~41% than IR66. Five lines, KR54-28-1, KR55-14-2, KR57-5-2, KR67-57-2 and KR128-19-1 were 5.33~6.06 ton/ha in rough rice yield. These high yield potential lines would be evaluated to adaptability in Cambodia, Laos, Myanmar and Vietnam during 2017.

• 한국작물학회지
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• 제66권2호
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• pp.130-137
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• 2021

본 실험은 지역 적응성 시험을 통한 도입 초당옥수수 자원의 농업 형질을 조사하고 혼합 선형 모형을 이용하여 조사 형질의 분산 구성요소를 추정하고 이를 통해 형질들의 유전력을 추정함으로써 신규 자원이 가진 육종재료로서의 가치를 평가하고, 이를 이용한 초당 옥수수 품종 육종 과정에서 선택할 수 있는 육종 및 선발 방법을 도모하고자 하였다. 1. 출웅기와 출사기를 제외한 모든 형질의 유전력은 낮게 추정되었는데 이러한 형질은 분산구성요소 중 유전분산이 낮게 추정되었다. 착수고율의 경우 품종과 지역 간의 유의한 상호작용효과로 인해 낮은 유전분산이 추정된 것으로 보인다. 2. 측정 형질의 낮은 유전력 추정치는 시험 재료가 모두 최신 상업용 품종이기 때문일 것으로 사료된다. 따라서 육종재료로서의 낮은 잠재력을 의미하는 것은 아니다. 3. 낮은 유전분산과 유의미한 상호작용 효과를 극복하고 선발 효율을 극대화 하기 위하여 교잡종의 직접적인 자가 수정을 통한 자식 계통 개발을 진행하기 보다 intermating을 통한 유전자 재조합을 먼저 유기하는 것이 바람직 할 것으로 보인다.

• Journal of Plant Biotechnology
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• 제38권2호
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• pp.137-142
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• 2011

Auxin is a group of small natural and synthetic molecules having diverse regulatory functions in plant growth and development. In this review, two auxin binding proteins identified by biochemical experiments to measure their auxin binding activities and biochemical functions are described. ABP1, a 22 kDa auxin binding protein, shows strong auxin binding affinity and possibly plays an important role in plant development, although its biochemical function are still unclear. ABP57, a 57 kDa soluble protein from rice shoots, has both of IAA binding activity and the plasma membrane proton pump activation. Although it is yet to be accomplished, the improvement of agronomic traits using auxin binding proteins is worth to be considered, since auxin is known to be related to such a diverse crop traits.

• 한국육종학회지
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• 제42권1호
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• pp.28-34
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• 2010

Diversity of 30 Korean potato cultivars was evaluated using 14 microsatellite markers. Twelve microsatellite markers representing 12 loci in the potato genome detected 84 polymorphisms among 30 cultivars and revealed alleles with a mean of 7.00 alleles per primer. The polymorphism information content (PIC) value ranged from 0.57 to 0.93 with average of 0.82. Based on polymorphism, cluster analysis was conducted by the unweighted pair-group method with arithmetic average (UPGMA) methods. Thirty potato varieties were distinctly separated into 2 groups and similarity coefficient of cluster ranged from 0.58 to 0.95. Thirty tetraploid cultivars were evaluated for six important agronomic traits. One-way analysis of variance was done to look for the degree of relationships between individual markers and traits. K1 and K2 markers showed a significant association with amylose contents, starch contents, and specific gravity.

• 한국작물학회지
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• 제51권4호
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• pp.335-339
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• 2006

The level of ${\beta}-glucan$ which is a major soluble dietary fiber found in the grain endosperm cell wall was highly variable among 25 barley genotypes grown at four locations including Suwon, Naju, Jinju, and Jeju. Statistically significant genotypic effects were observed for ${\beta}-glucan$ content at each or across growing sites (P<0.001). On average, 'Chalssalbori' showed the lowest percentage ${\beta}-glucan$ (4.04%) among genotypes in the grain, whereas 'Yonezawa Mochi' was highest in percentage ${\beta}-glucan$ (6.46%) compared to other genotypes. The significant difference between genotypes was approximately 1-2% across environments. The effects of location or interaction between locations and genotypes were not significant on the variation of ${\beta}-glucan$ contents. High ${\beta}-glucan$ content seemed to be greatly associated with such grain traits as waxiness and presence of husk except for 'Chalssalbori'. The waxy genotypes had a mean of 5.37% and values ranging from 5.28 to 5.47%, but normal genotypes had a mean of 4.78% and values ranging from 4.69 to 4.88% over environments. Hulless barley genotypes were also higher than hulled barley genotypes for the average ${\beta}-glucan$ content in both individual and over all environments. The difference between the hulled and hulless gene pools was on average of 0.37% with ranges from 0.19% to 0.56% at four environments. ${\beta}-glucan$ content measured from a mapping population of $F_5$-derived 107 lines derived from the cross between 'Yonezawa Mochi' and 'Neulssalbori' was not significantly associated with other agronomic traits except for 1,000-kernel weight at the '01 Suwon environment. Not too much information on the relationship of ${\beta}-glucan$ content to agronomic traits was available.