• Journal of the Korean Society of Tobacco Science
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• v.10 no.1
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• pp.21-26
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• 1988

Ten anther-derived doubled haploid (ADH) and 10 maternally-derived doubled haploid fines (MDH) from NC 2326 were evaluated in the field to compare their performance. Both anther-derived doubled haploid and maternally-derived doubled haploid lines were agronomically inferior to selfed parental variety for many parameters, but the degree of inferiority of the MDH lines were not significantly different from the selfed parental variety for any character investigated. The inferiority of the ADH lines were, however, significantly different from the selfed parental variety for yield, leaf length and width , and days to flower.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.179-184
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• 2004

A doubled-haploid (DH) population was developed through anther culture of F$_1$ plants obtained from a cross between a japonica cultivar, 'Nagdongbyeo', as male parent and a indica cultivar, 'Samgangbyeo', as female parent. Segregation modes for plant length, culm length, panicle length, third internode length, and days to heading in the DH lines showed nearly normal distribution with wide range of variation. A molecular map with 136 simple sequence repeat (SSR) markers was constructed using the DH population. The total map distance was 1,909 cM and the average interval of marker distance was 14 cM.

• Current Research on Agriculture and Life Sciences
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• v.31 no.2
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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.

• Korean Journal of Plant Tissue Culture
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• v.28 no.1
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• pp.37-40
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• 2001

To optimize the in uitro chromosome doubling procedure in anther cultures of rice, anthers were cultured on callus induction medium with 0.001 to 0.1 mg/L colchicine for 30 days. The addition of colchicine slightly reduced callus formation and plant regeneration in comparison to the colchicine-free medium (control medium). This reduction was greater with higher concentration colchicine. Microspore-derived rice plants in control medium were found to be mainly haploid (50 to 58.8%) and doubled-haploid (31 to 40%) in anther culture of 3 Japonica and 1 Tonsil type cultivars. The application of 0.001 mg/L colchicine was increased to 54.3∼60.0% in the frequency of fertile doubled-haploid plants. These results indicate that the addition of colchicine to the callus induction medium is an efficient means to obtain doubled-haploid plants in anther cultures of rice.

• Plant Breeding and Biotechnology
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• v.5 no.3
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• pp.204-212
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• 2017

There is a growing preference for using doubled haploids (DHs) in maize breeding programs because they reduce the time required to generate and evaluate new lines to 2 years or less. However, there is an urgent need for efficient techniques that accurately discriminate between haploid and diploid maize kernels. Here, we investigate the effects of several hormones and chemicals on the germination of haploid and diploid maize kernels, including auxin, cytokinin, ethylene, abscisic acid (ABA) biosynthesis inhibitor (fluridone), ABA catabolism inhibitor (diniconazole), methyl jasmonate (MeJA), and NaCl. Ethylene effectively stimulated the germination of both haploid and diploid maize kernels. The ABA biosynthesis inhibitor fluridone, the ABA catabolism inhibitor diniconazole, and MeJA selectively stimulated the germination of haploid maize kernels. By contrast, gibberellin, 1-naphthaleneacetic acid (NAA), kinetin, and NaCl inhibited the germination of both haploid and diploid maize kernels. These results indicate that the germination of haploid maize kernels is selectively stimulated by fluridone and diniconazole, and suggest that ABA-mediated germination of haploid maize kernels differs from that of diploid maize kernels and other plant seeds.

• Proceedings of the Korean Society of Crop Science Conference
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• 1997.05a
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• pp.24-25
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• 1997

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.4
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• pp.90-102
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• 2024

Haploid/double haploid plants developed from isolated microspores can significantly accelerate plant breeding. Haploid plants can naturally double their chromosomes to create a pure homozygous line of diploid plants. We present a method for producing embryos from isolated microspores of hot peppers (Capsicum annuumL.). We analyzed the polyploidization levels of the regenerated plants. The donor plants produced the optimal stage of microspores following short-term growth under low-intensity light, which resulted in high rates of embryogenesis and cotyledonary embryogenesis. To find an efficient culture method, liquid, doubled-layer, and 2-step cultures were tested. Liquid culture yielded the highest number of embryos, whereas the highest efficiency for cotyledonary embryogenesis was afforded by the doubled-layer culture. When normal cotyledonary embryos were transplanted onto a regeneration medium, they developed into complete plants. From these, 208 plants were tested via flow cytometric analysis, and 35.6% and 72.7% of the chromosomes from the Milyang-jare and LV2319 genotypes, respectively, were found to be spontaneous double haploids. These results are the same as those obtained on analyzing horticultural characteristics, including the size of leaves and the size and shape of fruits. The present study provides information on the practical application of isolated microspore culture of hot peppers, factors that affect embryogenesis, and methods for polyploidy testing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.250-253
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• 1998

Somaclonal variation was observed in the field on doubled haploid plants derived from single pollen of a rice cultivar "Hwaseongbyeo". The variations of seven quantitative traits including plant height and one qualitative trait (pubescence) in 436 lines ($R_2$ generation) were analyzed. The number of lines which fell beyond the boundaries of the 95% confidence intervals of the check variety, Hwaseongbyeo was checked for each quantitative trait, and of those fertility showed the highest variation frequency (85.6%), followed by plant height (77.5%), flag leaf length (66.5%), grains per panicle (42.2%), days to heading (34.5%), panicle length (30.7%) and panicles per hill (22.7%). And the variations of quantitative traits except days to flowering appeared to move in the negative direction compared to "Hwaseongbyeo". Variability within lines was also observed for quantitative and qualitative traits. Twenty-nine $R_2$ lines (7%) segregated for pubescence and 130 $R_2$ lines (30%) showed variation with regard to fertility. This suggests that mutations usually occur before diploidization. Twenty-nine $R_2$ lines representing a wide spectrum of variation were chosen for RAPD analysis. The number of lines showing DNA polymorphism compared to Hwaseongbyeo ranged 0 from to 10 according to the primer used and this seems to indicate that specific loci have highly mutable genomic site.utable genomic site.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.123-128
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• 2007

Demand for high quality rice has always been a major factor in the international rice marketing. In the present study, doubled haploid (DH) population derived from anther culture of a Tongil/japonica hybrid was used for genetic analysis of rice grain quality. The average values of DH lines for grain weight, grain length and the ratio of grain length to width were near the mid-parent value. More than 40% DH lines showed transgressive segregation for grain weight, length, amylose and lipid content, but less than 10% DH lines observed on ratio of length to width and grain thickness were transgressive segregation. Correlation analysis between appearance qualities and physicochemical characters indicated that grain width and grain thickness both significantly and negatively correlated to protein and lipid content. A highly significant negative correlation between protein content and amylose content was observed.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.180-180
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• 2003