‘Taoyuan No. 3-Spring Red’ and ‘Taoyuan No. 4-Red Glory’, the New Cultivars of Cherry Blossom in Subtropical Area

Cherry blossoms belong to the genus Prunus within the family Rosaceae. There are ∼100 species of indigenous plants, mainly distributed in temperate regions of the Northern Hemisphere, and there are more than 200 cultivated varieties (Obha et al. 2007). For blooming successfully in spring, it is necessary for those deciduous trees to undergo a period of chill beforehand. During the flowering period, the entire tree is devoid of leaves while the flowers blossom profusely on the branches, making it more aesthetically valuable. Cherry blossom viewing holds significant cultural importance in many temperate countries and plays a crucial role in international tourism activities (McClellan 2005). Taiwan is located at the junction of the subtropical and tropical climatic zones in the Northern Hemisphere, with the Tropic of Cancer, at the latitude of 23.5°, passing through the southern regions of Taiwan’s main island. The central and northern regions of Taiwan are characterized by a subtropical climate. According to the Flora of Taiwan (Editorial Committee of the Flora of Taiwan 1993), there are 11 native species of the Prunus genus in Taiwan. Among them, Taiwan cherry (Prunus campanulata Maxim) is distributed in southern China, Ryukyu Islands, and Japan, as well as in broad-leaved forests at high elevations (500–2000 m) throughout Taiwan (Editorial Committee of the Flora of Taiwan 1993). The native Taiwan cherry, displaying a range of flower colors from light pink to deep purple red, naturally blooms from January to March. Due to the mild winter climate in lower altitude areas of Taiwan, the selection of cherry blossom cultivars for landscape applications has been limited. Seed-propagated seedlings have been widely used for landscape purposes in urban and suburban areas, particularly in low-altitude regions (