Red skin coloration in pears is caused by anthocyanin accumulation, which contributes to antioxidant activity and enhances consumer preference because of its attractive appearance. However, anthocyanin levels are strongly affected by light, making it difficult to maintain stable coloration under bagging practices commonly used in Korea. In this study, we developed the first red-skinned pear cultivar in Korea, ‘Jungmojeoksaek1ho’ (Pyrus pyrifolia×(P. pyrifolia×P. communis)), and examined changes in anthocyanin content according to the timing of bagging. ‘Jungmojeoksaek1ho’ originated from a cross between ‘Manpungbae’ (P. pyrifolia) and ‘Oharabeni’ (P. pyrifolia×P. communis) in 2003 and was registered as a new cultivar in 2025 (Registration No. 10597). The trees were vigorous, with a spreading growth habit. The mean fruit weight was 291.5 g, lower than that of the control cultivar ‘Wonhwang’ (P. pyrifolia), with soluble solids content of 12.8° Brix and titratable acidity of 0.31%. Anthocyanin content analysis of the peel revealed that ‘Jungmojeoksaek1ho’ maintained high levels until 80 days after full bloom (DAFB), followed by a sharp decline. Bagging at 60 or 80 DAFB reduced anthocyanin accumulation, whereas bagging after 100 DAFB maintained relatively high levels in the later stages. These results suggested that bagging after 100 DAFB was optimal for achieving stable red coloration (Registration No. 10597).

Pears (Pyrus spp.) are economically important fruit trees grown extensively world-wide. To identify QTLs related to key agronomically important fruit traits, we conducted QTL analysis using an interspecific 178 F₁ populations derived from a cross between ‘Manpungbae’ and ‘Oharabeni’. Phenotyping data, including fruit weight, fruit length and diameter, fruit shape index (FSI), soluble sugar content, fruit firmness (FF), and titratable acidity (TA) were investigated from 2016 to 2018. Using the previously constructed genetic linkage map together with the three-year phenotypic dataset, we detected 14 significant QTLs associated with the control of fruit weight, fruit length and diameter, FSI, FF, and TA on linkage groups 3, 10, 11, 12, and 13. These findings provide a useful resource for advancing genetic and genomic studies in pears and will aid breeding efforts to improve major fruit traits.

Paprika (Capsicum annuum) cannot grow or set fruit in temperatures that are higher than the optimal level. This study assesses the characteristics of 52 paprika accessions introduced from the agrobiodiversity center and the world vegetable center during a high temperature period in order to develop heat tolerant lines. As a result of controlling the temperature in two greenhouses by side ventilation and fogging system, the average daily temperature of the high temperature regime was 34.3℃, which was 2.4℃ higher than that of the normal temperature regime. Plant height, stem diameter, fruit set, fruit weight, fruit shape, pericarp thickness, soluble sugar content, yield, and marketable fruit development rate were all investigated as vegetative and reproductive growth-related parameters. Plant height, fruit weight, pericarp thickness, and yield were all reduced during high temperature treatment. Six germplasm lines (T12, T15, T26, T29, T32, and T36) were selected as high-temperature tolerant lines based on these parameters. The selected lines will be used to breed heat-tolerant cultivars as well as crossbreeding for genetic analysis.

Watermelons are grafted to prevent soil-borne diseases such as Fusarium wilt (FW) and increase their resistance to abiotic stress. Root-knot nematodes (RKN) are a contributing factor to economic loss in several cucurbits, including watermelon. Growing resistance varieties is an effective way to reduce the damage caused by soil-borne diseases. Resistance evaluation was performed on 50 watermelon lines to select rootstocks resistant to FW and RKN. Fusarium oxysporum f. sp. niveum race 2 was inoculated into 10-day-old seedlings using a root dipping method, and resistance was evaluated for four weeks. The 37-day-old watermelon seedlings were inoculated with Meloidogyne incognita and evaluated 60 days later. Three lines (IT199860, PI296341-6, and PI532811) were resistant to FW race 2, while one line (PI494527) was moderately resistant. Three lines (PI296341-5, PI457916-2, and PI457916-5) were RKN resistant. The PI296341-6 line was selected for its resistance to FW and moderate resistance to RKN. These findings imply that the identified resistant lines can be used in rootstock breeding programs against FW and/or RKN.

Nowadays most parts of vegetable breeding in Korea have been conducted by private seed companies. However, in the beginning stages of breeding research, Horticulture Experiment Station played a crucial role. Major vegetable varieties that are distributed from Korea are produced as F₁ hybrids. Korea has developed leading techniques and human infrastructure for vegetable breeding. Such brilliant developments have resulted from three major factors: changes in the composition of varieties, the establishment of year-round vegetable production, and the development of the seed export market. First, an F₁ hybrid system increased seed performance more than traditional open pollinated (OP) varieties with respect to productivity, uniformity and disease resistance. Moreover, an F₁ hybrid system required repetitive seed production and provision, which increased the economic growth of seed companies. Second, vegetables tend to be consumed fresh instead of dried or processed. Finally, vegetable seed exports have continuously increased with the aid of R&D projects such as the Golden Seed Project (GSP). Therefore, for further progress of the vegetable industry, new varieties that can meet consumers’ demands, as well as the stable provision of fresh vegetables, are required. Contrary to the past, the future focus must be concerned with productivity and cultivation stability, the development of high value, functional, eco-friendly vegetables, and high quality vegetables. To cope with this, every breeding subject, including industry, universities, and institutes, have to collaborate with the aim of advancing vegetable breeding in Korea.

We developed high-quality Korean pepper (Capsicum annuum L.) varieties to compete with imported chili peppers from China. The ‘OH95’ line, which was introduced from Hungary in 1997, was self-pollinated, and the resulting ‘62067L2’ was selected as a pigment-rich maternal line in 2003. However, RSS and LV2319, both developed in 1993, were cross-bred, after which the paternal line ‘62027R3’ was developed by consecutive selections and generation advancement. After the cross combinations were performed, their horticultural characteristics were evaluated for two years, and subsequently, regional adaptation trials were conducted for at three different sites over three years. Of these, a new pepper variety, ‘Jeockyoung’ exhibited an average ASTA value of 175, representing pigment content, which was approximately 43% higher than that of a commercial cultivar ‘Manitta’. In addition, the capsaicinoid content of ‘Jeockyoung’ was 114.4±11.6 mg/100 g, which was slightly higher than that (86.3±2.8 mg/100 g) of the control cultivar. Moreover, regional adaptation trials revealed that the new variety showed regional differences in annual yield; however, the yield was approximately 18% higher than that of the commercial cultivar. Fruit weight, length, and diameter of the new variety were approximately 21.8 g, 14.3 cm, and 2.2 cm, respectively. The flowering period was approximately 101 days after sowing, which was similar to that of the control cultivar. In addition, leaf length and plant height were also not different from those of the control cultivar.

A new red butterhead lettuce (Lactuca sativa L.) with transverse broad elliptic, red leaves, ‘Sun Red Butter’, with late bolting and high yield, was developed from a cross between ‘Jajusangchu’ (red leaf color and half crisp) and ‘Dukseomjeokchukmyeon’ (high yield). The crossing and selection for advanced lines was previously carried out using the pedigree method during the period 2001–2009. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon-do, Gyeonggi-do, Chungcheongbuk-do, Jeollabuk-do, Gyeongsangnam-do, and Jeju-do) in 2011. The type of matured stage is early and medium butterhead lettuce. The shelf life of ‘Sun Red Butter’ was four weeks longer than that of ‘Germania’ at 4°C. The anthocyanin content of ‘Sun Red Butter’ was lower than that of ‘Germania’ at 11.2 mg/100 g. The BSL (latucin+8-deoxylactucin+lactucopicrin) content of ‘Sun Red Butter’ was higher than that of ‘Germania’ at 32.8 µg/g, DW. The marketable yield of ‘Sun Red Butter’ was higher than that of ‘Germania’ by 67% (at 621.4 g per plant), and ‘Sun Red Butter’ showed a particularly improved yield under high-temperature cultivation in the field. Furthermore, ‘Sun Red Butter’ had better taste characteristics and was crisper and sweeter than ‘Germania’. Therefore, we recommend that the new cultivar ‘Sun Red Butter’ would be suitable for cultivation in spring and fall. Furthermore, this new cultivar could be harvested in a single harvest, as in a head lettuce, and could therefore be managed more efficiently and economically by farmers.

A new lettuce (Lactuca sativa L.) variety ‘Sunny Red Butter’ that belongs to butter-head type has transverse broad elliptical leaf with red color. Crossbreeding of ‘Oriana’ and ‘Cardinale’ was made to obtain seeds of the F1 generation. Subsequent generations were selected using in pedigree methods until 2011, resulting in ‘Sunny Red Butter’. The new variety ‘Sunny Red Butter’ is brown in seeds and the upper part of the leaf is light red and glossy. The leaf stalk is white. It can be harvested from 30 days after planting. The average harvested leaf number is 51 leaves per plant. The average weight is 556.5g per plant, which is 44% higher than a control lettuce variety ‘Germania’. It showed that 30.9 tons/ha production was made in spring, summer, and autumn cultivations for 3 years in 6 areas (Daegwanryeong, Gyeonggi, Chungbuk, Jeonbuk, Gyeongnam, and Jeju) than the control variety ‘Germania’. The shelf-life of ‘Sunny Red Butter’ was 4 weeks for storage at 4℃. Anthocyanin amount (10.3 mg/100g) of ‘Sunny Red Butter’ was lower than that of ‘Germania’. BSL (latucin+8-deoxylactucin+lactucopicrin) amount of ‘Sunny Red Butter’, the bitter ingredients was 26.1 μg/g and higher than BSL amount of ‘Germania’. Leaf hardness of ‘Sunny Red Butter’ was 1,554 kg/cm 2 , which was thicker than ‘Germania’. ‘Sunny Red Butter’ showed better taste (more crispy and sweeter) than ‘Germania’. The new variety ‘Sunny Red Butter’ can be used as lettuce productions during spring and autumn in most area and in summer in highland of Korea.