Pepper mild mottle virus (PMMoV), a member of the genus Tobamovirus, is one of the most threatening pathogens affecting commercial pepper production, and it is classified into pathotypes P_1,2 and P_1,2,3. As chemical and physical treatments show limited success in controlling PMMoV, resistant pepper varieties are considered the most effective means of disease control. Two hundred pepper germplasms, including 167 accessions of Capsicum chinense and 5 reference accessions known as resistant L alleles, were assessed using a bioassay to select germplasms resistant to PMMoV. Six accessions, including IT261210, were resistant to both PMMoV pathotypes P_1,2 and P_1,2,3 as they developed necrotic local lesions only on inoculated leaves, whereas no symptoms were observed on the upper leaves. Moreover, RT-PCR results of the upper leaves of these accessions were also negative. Thus, the identified accessions may be a novel source of genetic resistance against present or emerging new pathotypes and may be useful for differentiating L alleles.

To compare agronomic and seed traits of 135 common bean landraces originating from Korea, Bulgaria, and El Salvador, we evaluated 20 morphological traits and performed principal component analysis (PCA). In the PCA, the first and second principal components accounted for 55.15% and 15.97% of the total variance, respectively. The first component showed a strong positive correlation with seed size and 100-seed weight, whereas the second component produced a strong negative correlation with days to flowering and days to maturity, indicating that these traits may explain the differences between landraces originating from different countries. Landraces from Korea showed higher variation in days to flowering and days to maturity; those from Bulgaria produced larger and heavier seeds; those from El Salvador produced smaller and lighter seeds and flowering and maturity occurred earlier. In addition, the landraces from El Salvador had relatively lower diversity compared to those from other countries, as they were grouped within a small cluster in the PCA. These evaluation results may provide important information for selecting breeding materials, and diversity analyses of landraces from different countries provide information for securing genetic resources.

Plant germplasm is a part of living genetic resources, including seeds and plant materials, such as roots, leaves, and stems, and should be conserved and managed to maintain ecological biodiversity and to consistently generate the product and supply food crops. Plant germplasm can be categorized based on various genetic traits such as race, and clustering based on similar genetic traits is an efficient method for managing large numbers of germplasms. Therefore, we developed an algorithm, termed cacGMS (Clustering Analysis for Categorical genetic traits of germplasms in Genebank Management System), using categorical variables which statistically differentiate the datatype of genetic traits such as seed-coat color, seed shape, and flower color. Briefly, using Newman’s modularity method, cacGMS combines the hierarchical clustering algorithm using the Ward2 method and representative-based algorithms such as K-medoids, and it regroups all germplasms using germplasm core sets. We tested cacGMS using 2,378 pepper germplasms with 46 different categorical genetic traits, and it exhibited better performance than the hierarchical and K-medoids algorithms for the average distance among clusters (0.4534) and entropy (1.2672). Moreover, cacGMS showed better performance in terms of threshold (from 15 to 30) for genetic traits than other algorithms and provided similar results in a test run using tomato germplasm. From these results, we expect that cacGMS will be a useful tool for managing each group with numerous plant germplasms and facilitate the analysis of other studies, such as analysis of representative characteristics of clustered germplasms and of correlations among germplasms in a particular cluster.

In Korea, black soybeans are traditionally consumed after cooking with rice to supplement protein and oil which are lacking in rice. Seed cooking quality including seed traits after cooking with rice, which is important for consumers, were so far not comprehensively considered during the process of breeding. In this study, we first evaluated seed quality after cooking with rice, we tested the correlation between seed cooking quality and seed water absorption ratio, and we attempted to identify the Quantitative trait locus(QTL)/gene using two recombinant inbred line (RIL) populations, i.e., Daepung × Socheong2 and Daepung × Ilpumgeomjeong. Based on phenotype and correlation analyses, the main factors affecting the hardness of soybeans cooked with rice may differ between RIL population. In the Daepung × Socheong2 RIL population, one QTL associated with seed hardness after cooking with rice was identified on chromosome 11, and Glyma.11g049600, encoding peroxidase, is proposed as a candidate gene. In the Daepung × Ilpumgeomjeong RIL population, two QTLs associated with seed hardness after cooking with rice were identified on chromosomes 7 and 19, one QTL related to seed water absorption on chromosome 3, and Glyma.19g092600 encoding pectin methylesterase inhibitor are proposed as candidate genes. This is the first study on soybean cooking quality after cooking with rice, and the locations of four related QTLs were identified. The results will be of use for future development of high-quality black soybean varieties with high consumer preference using molecular breeding methods.

Tofu is produced by mixing condensed soymilk with a coagulant. It has a low calorie and high protein and contains various important vitamins and minerals; therefore, consumption of tofu as a healthy and dietetic food has increased worldwide. For systematic application in breeding programs to increase tofu yield, evaluation of tofu characteristics is essential. To test the various characteristics of tofu, typically, a considerable amount of seeds (approximately 100 g, is required. Here, we propose a simple tofu quality test method requiring a small amount of seeds (15 g), which is 75% less than the amount needed for conventional testing. Tofu was manufactured using 20 soybean varieties with a conventional method (i.e., a tofu making machine, TM) and four simple methods: natural filtering (NF), weight pressure (WP), hand pressure (HP), and rotation machine (RM). The correlation between the five methods was assessed with respect to each tofu characteristic, and the HP and RM methods were statistically similar to the conventional methods, whereas the other methods showed differences. Regarding tofu yield, the HP and RM methods showed significantly higher correlation coefficients of 0.79 and 0.78, respectively, and the coefficient of variation between replications was also low. Therefore, the HP and RM methods were the best to easily characterize the tofu yield using a small amount of seeds. Considering the efficiency of the test, the RM method appears to be more effective than the HP method for testing multiple lines. These results will be used for the identification of quantitative trait locus/genes related to tofu quality and marker-assisted selection of breeding new soybean varieties.

‘Miwoo’ is a mid-late maturing, high-biomass-yielding rice (Oryza sativa L.) cultivar with high feed value and resistance to multiple diseases and insect pests. It was developed for use as whole crop silage (WCS) from a cross between ‘Suweon519’, a line with high biomass yield and multiple disease resistance, and ‘Suweon518’, a medium flowering, high yielding Tong-il type line, which is resistant to blast (BL), bacterial blight (BB) (race K1), rice stripe virus (RSV) and brown planthopper (BPH). In the central plain region of Suwon, ‘Miwoo’ cultivar exhibited a growth period of approximately 122 days from seeding to heading, culm length of 99 cm, panicle length of 28 cm, 12 panicles per hill, 143 spikelets per panicle, and 1,000-grain weight of 25.9 g as brown rice. This mid-late-flowering rice variety was resistant to lodging during the yellowing ripening stage, an optimal period for harvesting. In addition, ‘Miwoo’ was strongly resistant to leaf and neck blast, BB (race K1, K2, K3, K3a), RSV, BPH and small BPH. Its average dry matter yield over 3 years reached 19.9 MT/ha, which is 36% higher than that of ‘Nokyang’. ‘Miwoo’ is a high-amylose cultivar with 70.7% total digestible nutrients (similar to that of Nokyang) and grows well on the central and southern plains of the Korean Peninsula. It should be harvested 30 days after heading to improve its feed value and digestion rate in livestock. (Registration No. 7683)

A white sesame variety ‘Nuri (Sesamum indicum L.)’ with resistance to Phytophthora blight disease was developed in 2016. It was derived from a cross between ‘Suwon 131’ and ‘Yangbaek’ in 1999. ‘Nuri’ has few branches and triple capsules per node. Notably, ‘Nuri’ exhibited resistance to Phytophthora blight and Fusarium wilt and a yield of approximately 1.19 tons per hectare, 17% higher than that of ‘Kopoom’. ‘Nuri’ presented a crude fat content of 49.0% and protein content of 26.1%. Thus, this variety would contribute to increased sesame production. (Registration no. 7889).

In 2019, ‘Bodeuremi’ was developed as a high-yielding sweetpotato variety with good palatability. It was derived from a cross between ‘MI2006-58-02’ with high yield and ‘Beniharuka’ (IT309504) with good palatability. The storage roots of ‘Bodeuremi’ have a red skin, light orange flesh, and an ovate shape. When steamed, ‘Bodeuremi’ storage roots exhibit a moist texture and are more tender than those of the check variety ‘Pungwonmi’. The sugar content of steamed ‘Bodeuremi’ storage roots was 33.4 mg/100 g dw, which was 6.0% higher than that of ‘Pungwonmi’. The marketable yield of ‘Bodeuremi’ storage roots was 30.3 MT/ha in the early season culture, which was 4.5% higher than that of ‘Pungwonmi’ with high yield in the early season culture. ‘Bodeuremi’ is resistant to root-knot nematode and moderately resistant to Fusarium wilt. ‘Bodeuremi’ is expected to contribute to increased income of sweetpotato growers as it has high cultivation stability and can be shipped at a time when the market price is high owing to its high yield in the early cultivation.

A new malting barley variety, ‘Baegrok’, was developed in 2016 at the National Institute of Crop Science, RDA: Rural development administration by crossing the high-yield ‘Milyang130’ variety with ‘Myoginijo’, which has lodging tolerance and resistance to barley yellow mosaic virus (BaYMV). ‘Baegrok’ is suitable for use in brewing, similar to ‘Hopum’, and has resistance to powdery mildew and tolerance to lodging. From 2014 to 2016, regional yield trials were conducted in four different regions, with ‘Baegrok’ as a breeding line of ‘Iksan176’. The heading dates of ‘Baegrok’ in paddy and upland fields were April 6 and April 11, respectively, 2 days earlier than those of ‘Hopum’. Maturing dates of ‘Baegrok’ in paddy and upland fields were May 16 and May 21, respectively, similar to those of ‘Hopum’. The yield potential of ‘Baegrok’ was approximately 14% and 6% higher than that of ‘Hopum’ in upland and paddy fields. ‘Baegrok’ had a shorter culm length than ‘Hopum’ showing tolerance to lodging. Screening for powdery mildew resistance in the greenhouse showed that ‘Baegrok’ had resistance to powdery mildew, unlike ‘Hopum’ which was susceptible. It also is suitable for use in brewing, similar to Hopum. ‘Baegrok’ showed good grain quality in terms of β-glucan content (3.4%), starch (61.0%), and husk rate (12.7%). Regarding malt quality, ‘Baegrok’ exhibited 75.1% acrospire length, 70.8% friability, 4.4% soluble protein, and 345.8 WK (Windisch-Kolbach) diastatic power, superior to the malt quality of ‘Hopum’. Thus, ‘Baegrok’ is resistant to powdery mildew, tolerant to lodging, and more suitable for brewing. (Registration No. 8399)