Cultivated oat (Avena sativa L.) is an important cereal crop that has captured interest worldwide due to its nutritional properties and associated health benefits. Despite this interest, oat has lagged behind other cereal crops in genome studies and the development of DNA markers due to its large and complex genome. RNA-Seq technology has been widely used for transcriptome analysis, functional gene study, and DNA marker development. In this study, we performed the transcriptome sequencing of 10 oat varieties at the seedling stage using the Illumina platform for the development of DNA markers. In total, 31,187,392~41,304,176 trimmed reads (an average of 34,322,925) were generated from 10 oat varieties. All of the trimmed reads of these varieties were assembled and generated, yielding a total of 128,244 assembled unigenes with an average length of 1071.7 bp and N50 of 1752 bp. According to gene ontology (GO) analysis, 30.7% of unigenes were assigned to the “catalytic activity” of the parent term in the molecular function category. Of the 1273 dCAPS markers developed using 491 genotype-specific SNPs, 30 markers exhibiting polymorphism in 28 oat varieties were finally selected. The transcriptome data of oat varieties could be used for functional studies about the seedling stage of oat and information about sequence variations in DNA marker development. These 30 dCAPS markers will be utilized for oat genetic analysis, cultivar identification, and breeders’ rights protection.

Overexpression of Glu-1Bx7 via allele 1Bx7^OE significantly contributes to high dough strength in some wheat varieties and is useful for improving wheat quality. However, the proportion of wheat varieties containing Bx7^OE is quite low. In this study, four cultivars containing 1Bx7^OE were selected, and among the selected varieties, Chisholm (1Ax2*, 1Bx7^OE + 1By8*, and 1Dx5 + 1Dx10) was crossed with Keumkang, a wheat variety that contains 1Bx7 (1Ax2*, 1Bx7 + 1By8, and 1Dx5 + 1Dx10). SDS-PAGE and UPLC analyses showed that the expression of the high-molecular-weight glutenin subunit (HMW-GS) 1Bx7 was significantly higher in NILs (1Ax2*, 1Bx7^OE + 1By8*, and 1Dx5 + 1Dx10) compared with that in Keumkang. Wheat quality was analyzed with near infrared reflectance spectroscopy by measuring the protein content and SDS-sedimentation of NILs. The protein content of NILs (12.94%) was 21.65% higher than that of Chisholm (10.63%) and 4.54% higher than that of Keumkang (12.37%). In addition, the SDS-sedimentation value of NILs (44.29 mL) was 14.97% and 16.44% higher than that of Keumkang (38.52 mL) and Chisholm (38.03 mL), respectively. This study predicts that the quality of domestic wheat can be improved by crossbreeding with 1Bx7^OE-containing cultivars.

Grain protein content (GPC) is a quantitative trait that strongly influences wheat processing quality and end-product performance, but is highly affected by environmental conditions. This study aimed to identify QTLs associated with GPC using Korean wheat resources and assess the usefulness of linked markers for selection. A recombinant inbred line (RIL) population (F7 and F8; n=359) derived from ‘Joongmo2008’ × ‘Joah’ was genotyped with a 35 K SNP array, and QTL mapping was conducted using 4,891 filtered SNPs. Six QTLs were detected, and a major QTL on chromosome 3 B (Qgpc-3B) was consistently identified in both generations. Within the Qgpc-3B interval, lines carrying the ‘Joongmo2008’ alleles at AX-95163812 and AX-94495360 showed higher GPC, and the same trend was confirmed by a two-marker haplotype analysis. The direction of marker effects was also reproduced in a Korean wheat germplasm panel, suggesting that these markers have strong potential as practical selection indices for improving GPC in wheat breeding programs.

High temperature can impair grain development and storage compound accumulation during wheat grain filling, with responses depending on stress intensity, timing, duration, and cultivar. In this study, Saekeumkang and Hwanggeumal were selected from among major Korean wheat cultivars because they differ in grain quality- and starch-related characteristics, providing a basis for comparing cultivar-specific responses to heat stress during grain filling. Plants were exposed to 25/15, 35/25, and 40/30 °C (day/night) temperature regimes for 5 d beginning at 10 or 20 days after heading (DAH), and changes in grain morphology, endosperm and embryo development, 100-grain weight, protein concentration, and storage-related gene expression were evaluated. High temperature altered grain developmental traits and generally reduced 100-grain weight, while the magnitude of these effects differed between cultivars and treatment stages. Grain protein concentration and the expression of starch- and storage protein-related genes also showed cultivar- and stage-dependent responses. In a separate RNA-seq experiment initiated at 10 DAH, plants were exposed to the temperature treatments for either 5 or 10 d, and transcriptomic analysis revealed that heat intensity and exposure duration affected both the number and functional characteristics of differentially expressed genes, particularly those associated with protein folding and quality control, chromatin-related processes, and carbohydrate metabolism. These results indicate that heat responses during wheat grain filling are jointly influenced by developmental stage, exposure duration, and cultivar-specific molecular regulation.

Heading time is an important adaptive trait in wheat that is strongly influenced by vernalization requirement and photoperiod response and is closely associated with field growth dynamics. This study evaluated heading responses under controlled low-temperature and photoperiod conditions and monitored UAV-derived canopy development in 53 wheat genetic resources. Heading responses were assessed according to VRN1 and PPD1 genotype combinations under different low-temperature treatment durations and under 14 h and 16 h photoperiods after vernalization. Field growth was evaluated using UAV RGB images acquired in 2024–2025 and UAV multispectral images acquired in 2025–2026. Accessions lacking spring-type VRN1 alleles showed delayed heading under the control and short duration low-temperature treatments, whereas accessions carrying spring-type VRN1 alleles headed earlier. After vernalization, heading responses were more closely associated with the number of spring-type VRN1 alleles and PPD1 combinations than with the difference between the two photoperiod conditions tested. UAV RGB and multispectral variables captured temporal changes in canopy development and vegetation status. Multispectral-derived canopy coverage traits characterized variation in pre-winter establishment, relative winter decline, spring recovery, and seasonal canopy development among the wheat accessions. Overall, UAV-derived canopy traits provided complementary phenotypic information for characterizing field canopy development in wheat genetic resources.