The newly developed citrus cultivar, ‘Miraehyang’, was bred at the Citrus Research Center of the National Institute of Horticultural and Herbal Science (Jeju, Korea) by crossing ‘Ehime Kashi No.28’ (maternal parent) and ‘Hayaka Ponkan’ (paternal parent). The first fruiting of ‘Miraehyang’ occurred in 2016, and field evaluations were conducted until 2021. After final selection in 2021, the cultivar was officially registered for plant variety protection in 2024. The tree exhibits strong vigor, an open growth habit, and high fruit-bearing capacity. When grown in a plastic greenhouse, ‘Miraehyang’ showed minimal occurrence of puffing and fruit-cracking. New shoots emerged in late March, and flowering began in late April, with full bloom occurring in mid-May. The average fruit weight was between 150-200 g, and the fruit shape slightly flattened with a small apex. Coloring started in mid-October and completed by mid-December, resulting in a deep orange hue. The fruit is rich in juice with thin membranes, providing a tender texture. Under unheated greenhouse conditions, the fruit matured in mid-to-late December and had a soluble solids content of 12-13°Bx and acidity of approximately 1.0%. Peel thickness averaged at 3.3 mm, similar to that of ‘Ehime Kashi No.28’, but with improved ease of peeling. This cultivar is male-sterile, producing seedless fruit when grown alone. Similar to its maternal parent, ‘Ehime Kashi No.28’, ‘Miraehyang’ is susceptible to citrus canker but resistant to scab. ‘Miraehyang’ is expected to gain high consumer preference due to its ease of cultivation, superior peelability, and outstanding fruit quality and appearance (Variety registration number: 10180).
The ‘Minihyang’ mandarin is a new hybrid of ‘Kinokuni’בPonkan’ bred at the Citrus Research Institute, National Horticultural and Herbal Science, Korea. It has a small fruit size (30-40 g) and a high sugar content (12-14°Brix). Herein, a chemical characterization of ‘Minihyang’ was conducted. Free sugar, which determines sweetness, is a key component of food taste. Analysis of free sugar showed that the most abundant component was sucrose (8.81±0.45 g/100 g), followed by glucose (1.23±0.11 g/100 g), and fructose (1.23±0.08 g/100 g). Among the 20 free amino acids analyzed, arginine and asparagine accounted for 71% of the total amino acid content, displaying both amino acids at the highest content of 77.14 mg/100 g. The major flavonoids in citrus fruits differ between varieties, showing the differences among cultivars. The flavonoid contents of ‘Minihyang’ were higher in the peel than in the flesh, and hesperidin was identified as the major flavonoid, with 1,133.7 and 689.8 mg/100 g extracted from the peel and flesh, respectively. Furthermore, nobiletin and tangeretin, which are only present in citrus species, were identified in the peel. Volatile component analysis revealed that limonene content, a characteristic component of citrus fruits, was highest in the flesh of ‘Minihyang,’ accounting for approximately 75-80% of all volatile compounds. Notably, the order was fresh limonene>terpinene>terpinolene. Overall, this study revealed many functional compounds in the ‘Minihyang’ mandarin hybrid.