‘K-Ol2’ is a high-oil, high-oleic acid peanut (Arachis hypogaea L.) variety developed by the National Institute of Crop and Food Science and released in 2022. This variety was derived through pedigree selection from a single cross between the variety ‘Jaseon’ and the high-oleate elite line ‘YG377’. High-oleate lines were selected in the F₃ generation using Near-Infrared Spectrophotometry and gas chromatography. ‘K-Ol2’ exhibits a relatively short plant height with main stem and branch lengths of 29 cm and 36 cm, respectively, which are less than those of the check variety ‘Akwang’. The seeds had a brown testa and an elliptical kernel shape, with a 100-seed weight of 87 g and an average of 54 mature pods per plant. Seed composition analysis revealed an average protein content of 29.3% and a high crude fat content of 54.5%. The oleic acid (C18:1) content reached 82.8%, with an oleic to linoleic acid ratio of 28.5:1, significantly higher than that of ‘Akwang’ (2.2:1). In oxidative stability evaluations under accelerated oxidizing conditions, ‘K-Ol2’ exhibited an extended induction time to reach maximum conductivity increase, indicating improved resistance to lipid oxidation. Regional yield trials conducted from 2020 to 2022 demonstrated that ‘K-Ol2’ produced an average yield of 4.60 MT⋅ha^-1, representing a 10% increase over ‘Akwang’. Due to its high oil content and improved oxidative stability, ‘K-Ol2’ is expected to play a valuable role in the peanut processing industry (Registration No. 10358).

In 2020, ‘Sodammi’ was developed as a sweetpotato with a slightly moist texture, excellent palatability, and appearance. It was derived from a cross between ‘Hogammi’ (IT327288), which has a slightly moist texture and excellent palatability, and ‘Kyushu No. 121’ (IT309496), which has a yellow flesh and good appearance. The storage roots of ‘Sodammi’ have a purple-red skin, yellow flesh, and an ovate shape. ‘Sodammi’ storage roots exhibit a slightly moist texture and are more tender than those of the check variety ‘Jinhongmi’. The sweetness of steamed storage roots of ‘Sodammi’ was 19.1, which was 24.8% higher than that of ‘Jinhongmi’. Palatability of steamed storage of ‘Sodammi’ was better than that of ‘Jinhongmi’. The marketable storage root yield of ‘Sodammi’ was 19.6 MT/ha during the normal season culture. ‘Sodammi’ is moderately resistant to Fusarium wilt and root-knot nematodes. ‘Sodammi’ had very good storability, as there was almost no decay rate and no internal cavitation during long-term storage. Cultivation of the ‘Sodammi’ variety is expected to expand considerably, as it has characteristics favored by consumers, farmers, and distributors due to its excellent palatability, appearance, and storability (Registration No. 8789).

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.

In order to select sweetpotato varieties with excellent tip characteristics, we investigated the appearance, yield, and functional compounds in 32 domestic sweetpotato varieties. During the cultivation period, the total production of sweetpotato tips among the different variety ranged from 1,780 to 9,923 g/m², with that of the Gogeonmi variety being the highest. The lutein content among varieties ranged from 21.7 to 47.0 mg/100 g and was highest in the Juhwangmi variety, whereas the ß-carotene content ranged from 25.5 to 183.4 mg/100 g and was highest in the Hayanmi variety. The total polyphenol content ranged from 30.7 to 74.4 mg CAE/g, and it was high in the Pungwonmi, Daeyumi, and Dahomi varieties at 74.4, 73.8, and 72.9 mg CAE/g, respectively, whereas the DPPH radical scavenging activity of tips ranged from 88.6% to 91.6%, with Gogeonmi and Healthymi showing the highest value of 91.6%. ABTS radical scavenging activity was found to be lowest in the Yeonjami variety at 86%, whereas the remaining 31 varieties showed values in excess of 96%. ABTS radical scavenging activity showed a high positive correlation with total polyphenol content. On the basis of these analyses, we identified Juhwangmi with high lutein content, Hayanmi with high beta-carotene content and high yield, and Gogeonmi with high DPPH radical scavenging activity and high yield, as being suitable varieties for tip cultivation. We anticipate that these sweetpotato varieties with excellent tip characteristics will be used as parents for the breeding of varieties for vegetable use.

AbstractIn 2016, ‘Jinyulmi’ was developed as a sweetpotato variety with good palatability and high marketable storage root yield. It was derived from a cross between ‘Sinchunmi’ and ‘Jeonmi’. ‘Sinchunmi’ is small, with an average storage root weight of 141 g and an average number of marketable storage roots of 3.4. ‘Jeonmi’ has a high storage root yield of 26.2 MT/ha and intermediate steamed storage root texture. The storage roots of ‘Jinyulmi’ are elliptical and have red skin and yellow flesh. ‘Jinyulmi’ is resistant to Fusarium wilt and moderately resistant to root-knot nematode. The steamed storage root texture of ‘Jinyulmi’ is intermediate and more tender than that of check variety ‘Yulmi’. The sweetness of ‘Jinyulmi’ steamed storage roots was 13.1, which was 12.9% higher than that of ‘Yulmi’. ‘Jinyulmi’ steamed storage roots are also more palatable than those of ‘Yulmi’. The marketable storage roots yield of ‘Jinyulmi’ was 24.2 MT/ha in the early season culture, which was 26.0% higher than that of ‘Yulmi’. Its average marketable storage root weight was 137 g in the normal season culture, which was lower than that of ‘Yulmi’, but the number of marketable storage roots per plant was 3.6, which was higher than that of ‘Yulmi’. The marketable storage root yield of ‘Jinyulmi’ was 28.6 MT/ha in the normal season culture, which was 19.7% higher than that of ‘Yulmi’. ‘Jinyulmi’ is, therefore, suitable for both early and normal season cultures (Registration No. 7053).

‘Danjami’ was developed in 2015 as a purple-fleshed sweetpotato variety with excellent palatability. It was derived from a cross between ‘Yeonjami’ with purple flesh and ‘Yeonhwangmi’ with good palatability. The storage roots of this variety are elliptical with purple skin, and light purple flesh. It is moderately resistant to fusarium wilt and resistant to root-knot nematode. The texture of the steamed storage root of ‘Danjami’ is slightly moist and more tender than that of ‘Sinjami’. Soluble solid content of steamed storage roots of ‘Danjami’ was 31.3 °Brix, which was 20.8% higher than that of ‘Sinjami’. The palatability of steamed storage roots of ‘Danjami’ was better than that of ‘Sinjami’. The anthocyanin content of storage roots of ‘Danjami’ was 55.1 mg/100g dry weight. Total polyphenol content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity did not differ from that of ‘Sinjami’. The number of marketable storage roots per plant and the average weight of marketable storage root was 2.8 and 136 g under the normal and late-season culture in ‘Danjami’, respectively. The marketable storage root yield of ‘Danjami’ was 21.5 MT/ha under the normal and late-season culture, which was 78.8% of that of ‘Sinjami’. The yield of marketable storage root over 50 g of ‘Danjami’ was 15.3 MT/ha under the early-season culture, which was 28.8% lower than that under the normal and late-season culture. ‘Danjami’ was more suitable for the normal and late-season culture than for the early-season culture (Registration No. 6465).

‘Hogammi’ was developed as a sweetpotato variety with β-carotene content and excellent palatability in 2015. It was derived by crossing ‘AB95007-2’, which has good shape and storage root yield, and ‘Annoimo’, which has light orange flesh and good palatability. ‘Hogammi’ had storage roots with long elliptical shape, red skin, and light orange flesh. The texture of the steamed storage root of ‘Hogammi’ was intermediate or slightly moist, and it was more tender than that of ‘Yulmi’. The soluble solid content of the steamed storage roots of ‘Hogammi’ was 29.7 °Brix, which was 10.8% higher than that of ‘Yulmi’. The palatability of the steamed storage roots of ‘Hogammi’ was better than that of ‘Yulmi’. The β-carotene content of the storage roots of ‘Hogammi’ was 9.8 mg/100 g dry weight. ‘Hogammi’ was moderately resistant to Fusarium wilt and root-knot nematode. In ‘Hogammi’, the number of marketable storage roots per plant and the average weight of marketable storage root were 3.4 and 133 g under culture in the normal season, respectively. The marketable storage root yield of ‘Hogammi’ was 24.1 MT/ha under culture in the normal season, which was 4% higher than that of ‘Yulmi’. The yield of marketable storage root over 50 g of ‘Hogammi’ was 14.5 MT/ha under culture in the early season, which was 39.8% lower than that under culture in the normal season. ‘Hogammi’ was more suitable for culture in the normal season (Registration No. 6466).

This study was carried out to establish the optimal conditions for callus induction and plant regeneration using immature inflorescence of M. sacchariflorus cv. ‘Wooram’, a bioenergy crop selected in Korea. Callus induction rate was the highest (93.3%) in MS medium containing 3 mg L^-1 2,4-D, and 86.7% in MS medium containing 3 mg L^-1 2,4-D combined with 0.1 mg L^-1 BA. Plant regeneration rate was high when the calli derived from the medium containing BA was used, as compared with those derived from the BA-minus medium. The results showed that the medium conditions containing 5 mg L^-1 BA combined with 0.1 mg L^-1 NAA was the most effective in plant regeneration of which the rate reached 86.7%. The regenerated shoots were separated from the calli and roots over 3 cm were developed from the shoots after 4 week culture on basal MS medium without supplementation. The plantlets were then transferred to soil and cultured in greenhouse. After 5 weeks, the plants with the height of at least 20 cm were successfully acclimatized.