• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.246-246
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.239-239
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.132-132
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• 2023

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.89-94
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• 1998

Granule bound starch synthase (GBSS), also known as the '"waxy protein'", is responsible for the synthesis of amylose in the amyloplasts of cereal crops. In hexaploid wheat (Triticum aestivum L.), GBSS is involved in amylose synthesis and rolls as an important factor to determine flour quality and end-use quality in food products. Genes on three Wx loci have been found to encode GBSS in common wheats. We developed techniques for the purification and separation of GBSS in wheat. Three major GBSS isoforms, which were encoded by the genes on three loci, Wx-A1, Wx-B1, and Wx-D1 migrating differently by one dimensional SDS-po-lyacrylamide gel electrophoresis (1D SDS-PAGE), were identified. GBSS from 66 Korean hard and soft winter wheats were purified and determined for their Wx loci and four of them were identified possessing a null allele either at the Wx-A1 and Wx-B1 loci. With help of identification of three GBSS isoforms using 1D SDS-PAGE system, we are able to identify and monitor Wx gene expressions in breeding materials for developing waxy or partial waxy wheats without experiencing consecutive selecting generations.cting generations.

• Journal of Plant Biology
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• v.39 no.2
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• pp.113-121
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• 1996

The role of Ca2+ on benzyladenine (BA)-induced senescence retardation in mature wheat (Triticum aestivum L.) primary leaves was investigated. When an extracellular calcium chelator, ethylene glycol-bis-($\beta$-aminoethylether)-N, N'-tetraacetic acid (EGTA) together with BA, was applied to senescing leaves for 4 days of dark incubation, the content of chlorophyll and soluble protein decreased rapidly. And, the content of malondialdehyde (MDA), known to be a degradation product of membrane lipids, increased compared with the BA alone control. The BA-EGTA combination also caused the stimulation of protease and RNase activity and a rapid loss of catalase activity owing to the decling of BA effects. In the case of treatment with only intracellular calcium antagonist 3, 4, 5-trimethoxybenzoic acid 8-(diethylamino) octyl ester (TMB-8) without the BA addition, the chlorophyll content at day 4 after dark incubation decreased in paralled with the increasing concentration of the antagonist. In addition, the chlorophyll content at 10-5 M calcium ionophore A23187 treatment in the absence of BA was similar to that of the BA alone treatment. These results suggest that calcium may mediate the retardation effect of BA on leaf senescence by acting as a second messenger and that the calcium input from cell organelles, as well as the calcium inflow from intercellular spaces and cell walls, may be involved in modulating cytosolic calcium levels related to BA action.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.393-397
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• 2016

Whole grain wheat flour (WGWF) is the entire grain (bran, endosperm, and germ) milled to make flour. The WGWF of 31 Korean wheat (Triticum aestivum L.) cultivars were analyzed for the chemical compositions, and classified into groups by hierarchical cluster analysis (HCL). The average composition values showed a substantial variation among wheat varieties due to different wheat varieties. Wheat cv. Shinmichal1 (waxy wheat) had the highest ash, lipid, and total dietary fiber contents of 1.76, 3.14, and 15.49 g/100 g, respectively. Using HCL efficiently classified wheat cultivars into 7 clusters. Namhae, Sukang, Gobun, and Joeun contained higher protein values (12.88%) and dietary fiber (13.74 %). Regarding multi-trait crop breeding, the variation in chemical compositions found between the clusters might be attributed to wheat genotypes, which was an important factor in accumulating those chemicals in wheat grains. Thus, once wheat cultivars with agronomic characteristics were identified, those properties might be included in the breeding process to develop a new variety of wheat with the trait.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.277-286
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• 2023

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease in wheat worldwide. In April 2021, tan spot symptoms were observed in a commercial wheat field in Suncheon, Jeonnam Province, Korea, with over 5% of the wheat leaves exhibiting symptoms. These symptoms included oval-shaped tan necrosis surrounded by a bright halo. The three representative isolates exhibited irregular mycelial growth on V8-potato dextrose agar and produced pseudothecia. Based on the concatenated sequence datasets of four multi-genes, including the internal transcribed spacer, large subunit ribosomal RNA, glyceraldehyde-3-phosphate dehydrogenase, and RNA polymerase II second-largest subunit genes, phylogenetic analysis revealed that these three isolates clustered in the same clade as P. tritici-repentis. Results of pathogenicity test indicated that the initial symptoms appeared 5 days post-inoculation (dpi), with typical tan spot symptoms developing at 7 dpi. The pathogen was successfully re-isolated from the symptomatic tissues, thus fulfilling Koch's postulates. Furthermore, we selected three fungicides that effectively inhibited the mycelial growth of P. tritici-repentis by more than 90% in vitro. To the best of our knowledge, this is the first report of tan spot disease in wheat in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.120-123
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• 1998

Based on the co-linearity in the Triticeae, comparative RFLP analysis of 2M chromosome of Ae. comosa Sibth et Sm. was performed with 2MS and 2M additional lines of Triticum aestivum L. cv. Chinese Spring. Among the wheat RFLP probes conserved in the short arms of wheat chromosome 2, those above psr912 were located on the long arms of 2M in Aegilops comosa. The rest probes on the short arm and all the probe sequences on the long arm of group 2 chromosome in wheat were conserved on the equivalent chromosomal position in Aegilops comosa. So, it is apparent that some chromosomal segment from the short arm had been transferred to long arm while reconstructing 2M chromosome relative to wheat chromosomes. The break-point was located between psr912 and psr131 of the short arm. This rearrangement of chromosome 2M might be a molecular evidence of the M genome speciation from an ancestral type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.2
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• pp.35-41
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• 1979

To observe the effects of temperature and photoperiod on the growth and yield of winter wheat (Triticum aestivum, L) eight varieties including Chang Kwang were tested at various treatments like longday-high temperature (24hrs-20\circ), shortdayhigh temperature (12hrs-20\circ), longday-low temperature (24hrs-14\circ) and shortday-low temperature (12hrs-14\circ). Among the traits measured, days to heading, plant height, spike length, number of spikes per hill and grain yield per hill were generally decreased at high temperature and long day treatment and increased at low temperature and shortday condition. Number of grains per spike was decreased at low temperature and short day condition while increased at longday and high temperature conditions. Grain weight was decreased significantly at high temperature and shortday while increased at low temperature and longday treatment.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.737-744
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• 2015

The purpose of this study was to evaluate the phenolic compounds and radical scavenging activity of the Korean wheat (Triticum aestivum L.) according to germination times. The cultivated varieties were T. aestivum L. cv. Keumkang, Jokyung, Baekjoong, and Goso. The total polyphenol, flavonoid, and tannin contents of the ethanolic extracts of wheat were significantly increased with longer germination times. The total polyphenol contents of ungerminated Keumkang, Jokyung, Baekjoong, and Goso were 13.74, 15.05, 16.84, and 13.02 mg GAE/100 g, respectively, and the contents in germinated wheats increased with longer germination times. The total flavonoid contents of ungerminated wheats were 5.11, 6.72, 6.28, and 5.43 mg CE/100 g, and the total tannin content was 9.19, 8.86, 8.93, and 8.66 mg TAE/100 g, respectively. The total flavonoid and tannin contents were substantially increased with longer germination times. The DPPH radical scavenging activity of ungerminated Keumkang, Jokyung, Baekjoong, and Goso was 30.77, 23.88, 25.35, and 18.73 mg TE/100 g, and the activity in wheats germinated at $25^{\circ}C$ for 72 hours was 47.47, 44.17, 38.22, and 42.85 mg TE/100 g, respectively. The ABTS radical scavenging activity of ungerminated wheats was 3.42, 88.53, 88.87, and 79.97 mg TE/100 g, respectively, and the activity in germinated wheats increased with longer germination times.