The composition of high-molecular-weight-glutenin subunits (HMW-GS) is a key determinant of wheat baking properties. These subunits are encoded by the GLU-A1, GLU-B1, and GLU-D1 loci on the long arm of chromosome 1 and consist of x- and y-type subunits. Allelic variations in composition are a major factor influencing bakery quality. Unlike sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) or ultra-performance liquid chromatography (UPLC), which often fail to resolve closely related allelic variants, PCR-based markers allow for clear and definitive discrimination at the DNA level. Building on the results of a previous study that determined the GLU-B1 allele composition, we aimed to confirm—through the use of PCR markers—the allele compositions of GLU-A1 and GLU-D1 in 44 domestic wheat varieties. The results showed that “Jonong” and “Sinmichal1” contained the Glu-A1b (A1x2*) allele rather than Glu-A1a (A1x1) or Glu-A1c (A1x-null). Additionally, “Jonong” and “Sinmichal1” exhibited the allelic composition Glu-D1a (D1x2+D1y12), rather than Glu-D1d (D1x5+D1y10) or Glu-D1f (D1x2.2+D1y12). These results were compared with those obtained by SDS-PAGE and UPLC. The PCR-based markers used to identify GLU-A1 and GLU-D1 alleles in this study will be valuable for determining the allelic composition at the GLU-A1 and GLU-D1 loci in domestic wheat varieties. Furthermore, the re-evaluated genetic composition is expected to improve the precision of assessments related to the baking quality of domestic wheat.

In common wheat (Triticum aestivum L.), the protein content and glutenin protein composition are the key quality-determining parameters. Allelic variations, especially in high-molecular-weight glutenin subunits (HMW-GSs), affect bread quality significantly. The HMW-GS Glu-1 locus consists of two tightly linked genes encoding x- and y-type subunits that exhibit highly variable frequencies. In this study, we evaluated Glu-B1 alleles using allele-specific PCR markers in 44 domestic wheat cultivars. The composition of Glu-1Bx7+Glu-1By8 in the 24 cultivars was either Glu-1Bx7+Glu-1By8, Glu-1Bx7*+ Glu-1By8, or Glu-1Bx7*+Glu-1Bx8*. In addition, the two cultivars initially identified Glu- 1Bx7+Glu-1By8* were corrected to Glu-1Bx7*+Glu-1By8*. Seven cultivars previously classified as having Glu-1Bx7+Glu-1By9 composition contained Glu-1Bx7*+ Glu-1Bx9. The allele composition of the cultivar was identified as Glu-1Bx20+Glu-1By20 instead of Glu-1By20. The HMW-GSs of 21 wheat varieties were analyzed using ultra-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results will be helpful for evaluating the composition of Glu-B1 alleles in domestic wheat and accurately assessing the quality of domestic wheat flour.

Fusarium head blight (FHB) causes yield reduction, quality deterioration, and mycotoxin contamination in wheat, highlighting the need for resistant wheat varieties. In this study, we evaluated FHB resistance genes and infection rates in 44 domestic wheat varieties. Among them, 42 had the Type I resistance gene Fhb4, 37 had Fhb5, and 35 possessed both. For Type II resistance, 14 had Fhb1, 11 had Fhb2, and five had both. Twenty cultivars had both type I and type II resistance genes, and among them, Chungkye, Dahong, Gobun, Namhae, and Ol had all of the Fhb1, Fhb2, Fhb4, and Fhb5 genes. The average infection rate over three years was 42.6% in cases with both Type I and Type II resistance genes and 44.3% in cases without Type II resistance genes. The infection rate was very high in 2020 and very low in 2021, complicating the analysis of the three-year average. However, when the infection rate was evenly distributed in 2019, there was a tendency for increased resistance among the varieties carrying Type II resistance genes. This suggested that external factors may influence infection rates, emphasizing the need for a precise evaluation system suitable for selecting additional resistance genes. In addition, it is necessary to develop resistant varieties suited to the domestic environment through additional resistance gene selection and integration of resistance genes. This study contributes to understanding FHB resistance genes in domestic wheat varieties and developing resistant domestic wheat varieties.

Gluten proteins in wheat grains are generally considered one of the most important factors in determining dough properties and bread quality. In this study, wheat protein quality characteristics were investigated in 607 varieties collected from seven countries grown in a South Korean wheat breeding field for two years. The average protein content was 12.2±1.86%, and the sodium dodecyl sulfate-sediment volume (SDSS) was 46.9±8.39 mL. HI-LINE had the highest protein content (18.3±0.35%) and SDSS (76.7±1.98 mL), while both NE 84557 and Iksan 374 showed small deviations in protein content and SDSS. Protein content and SDSS values were higher in Ax2*+By8 and By9+Dy10 combinations at Glu-A, Glu-B1, and Glu-D1 loci of high molecular weight gluten subunit (HMW-GS) than in other combinations. However, no difference in Glu-A3 and Glu-B3 loci in LMW-GS was observed. Furthermore, in HMW-GS, the composition of Glu-D1 Dy10 and Dy12 had a greater effect on protein quality than Glu-B1 By8 and By9 when the allele of Glu-A1 had Ax2*. Significant differences were found between Dy10 and Dy12 genes of the HMW-GS Glu-D1 and between protein content and SDSS, but not among others. These results suggest that Glu-D1 is extremely important for improving protein quality in HMW-GSs. As a result of this study, HMW-GS allele selection using functional markers, protein content, and SDSS investigation are expected to enable the development of varieties with high protein quality that are stable amid various environmental changes.

This study aimed to develop an agarose gel-based multiplex PCR assay using sequence-tagged site (STS) and simple sequence repeat (SSR) markers that can differentiate Korean wheat cultivars. Forty-nine Korean wheat cultivars were primarily classified based on seed coat color into red (36) and white (13) groups. Red wheat cultivars were further differentiated by three multiplex PCRs using molecular markers for Ppo-A1/Vrn-D1a/Rht-B1b, Glu-A3ac/TaCwi-A1b/Lr34, and Glu-A1ac/Glu-B1b/KWSM003/TaSE96. Similarly, white wheat cultivars were further differentiated using two multiplex PCRs using the molecular markers for Ppo-A1/Vrn-D1a/Pina-D1a and Ppo-B1/Glu-B3h. A multiplex PCR assay using molecular markers for Glu-A1b/Glu-D1d/Wx-B1 was developed to differentiate four Korean wheat cultivars used as government certified seeds: Baekkang, Hwanggeumal, Keumkang, and Saekeumkang. A multiplex PCR assay using molecular markers for Glu-B3h and Pin-D1a was used for colored wheat cultivars, Arijinheuk, Ariheuk, and Chinese colored wheat. The multiplex PCR assays developed in this study can provide useful molecular tools for differentiating Korean wheat cultivars, developing wheat seed management systems, and guaranteeing wheat seeds in Korea.

The 12 cultivars of the Jeju native Citrus are considered to have originated from China. However, the origin of the cultivar ‘Byungkyool’ (Citrus platymamma Hort. ex Tanaka) is not clearly known. We performed PCR analysis by using three primer sets designed from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) to analyze the phylogenetic relationship between the traditional citrus cultivars and the Byungkyool cultivar. Sequence length of the nrDNA ITS1 region of JNCPCRI (Jeju Native Citrus platymamma Citrus Research Institute) cultivar was 247 bp, 8the ITS2 region was 228 bp and the total ITS region (ITS1-5.8S-ITS2) was 638 bp. Analysis of the genetic relationship based on the sequence analysis at the ITS region of the JNCPCRI cultivar revealed that the ITS1 region of the cultivar was genetically the same as that of the Byungkyool (JQ990189) cultivar, and the ITS2 region was genetically similar to the Binkyool (JQ990180), Hongkyool (JQ990178), Dangyooja (JQ990179), and Pyunkyool (JQ990181) cultivars. Moreover, the total ITS region in the 5.8S rDNA region was genetically similar to the Hongkyool (JQ990178) cultivar. In addition, the total ITS region of the JNCPCRI cultivar was the most closely related to the Cheongkyool (JQ990183) cultivar and has been reported to originate from the Binkyool (JQ990180) and Pyunkyool (JQ990181) cultivars. Although the JNCPCRI cultivar was morphologically the same as the Byungkyool (JQ990189) cultivar, the ITS region showed genetic heterogeneity. Taken together, we conclude that the genetic variation in the ITS region of JNCPCRI cultivar suggests that it was propagated through fertilization with the surrounding citrus cultivars.

In this study, we compared disease incidence rate and phyllosphere microbial community between drought resistance transgenic rice (Agb0103) and non-transgenic Ilmi (NGM) during 2011-2014 to examine an environmental risk assessment of drought resistance transgenic rice (Agb0103). As the results, major diseases such as sheath blight, brown spot, leaf blast and false smut were occurred, however, there were no significant disease incidence rate between Agb0103 and NGM. As the results of counting bacterial and fungal viable cell, the colonies were increased or decreased which affected by environmental conditions, however there were no differences between Agb0103 and NGM. Also unweighted pair-group method with arithmetic averaging (UPGMA) analysis based on polymerase chain reaction with denaturing gel electrophoresis (PCR-DGGE) revealed that DGGE band pattern of bacterial and fungal communities were clustered by each month and there were no differences between Agb0103 and NGM. Furthermore, isolated casual agents causing sheath blight and brown spot were collected from Agb0103 and NGM, and they revealed that each of pathogens were no differences in morphology and pathogenicity. Therefore, our results suggested that Agb0103 showed no differences in disease incidence rate, characteristic of pathogens and phyllosphere community with NGM. In this way, it can be assumed that transgenic rice Agb0103 could not influence phyllosphere microorganism community and environmental conditions.

Apple (Malus × domestica Borkh.) has gametophytic self-incompatibility (S) controlled by the multi-allelic S-locus. In the present study, S-genotypes of 24 apple cultivars including newly released Korean cultivars and seven crabapple cultivars were identified using S-allele specific polymerase chain reaction analysis. Twelve different S-alleles (S₁, S₂, S₃, S₅, S₇, S₉, S₁₀, S₁₆, S₂₁, S₂₃, S₂₆, and S₂₉) from 31 apple and crabapple cultivars were identified using 23 S-allele specific primers. Among them, S₁ (41.7%), S₃ (58.3%), S₇ (29.2%), and S₉ (54.2%) S-alleles were found to be common in 24 apple cultivars. The newly released Korean cultivars ‘Arisoo’ and ‘Hwangok’ were genetyped as S3S7 and S3S9, respectively. S-genotypes information obtained from the present study will be useful to select proper pollinzers for stable production of apple fruit and to design cross of breeding programs.