Ning Qing 3: A New Holly Cultivar with Peculiar Leaf Morphology

Abstract

The Ilex L. (holly) is the largest woody dioecious angiosperm genus in Aquifoliaceae, composed of ∼700 deciduous and evergreen trees and shrubs (Chong et al. 2022; Manen et al. 2010; Yao et al. 2022). The genus is distributed worldwide from tropical to temperate regions, with centers of species diversity located in East Asia and South America (Su et al. 2020; Yao et al. 2016). For tens of decades, Ilex species have been used as ornamentals, beverages, pharmaceutical plants, and industrial materials (Li et al. 2022; Yao et al. 2022; Zhou et al. 2022). The flowers and fruits of holly are fairly uniform, but leaf characters vary greatly among species in this genus, including size, shape, margins, and texture. Many Ilex species are widely cultivated as ornamental plants because of their red drupes and often distinctive leaves. Therefore, many breeders and consumers pay much attention to the leaf traits of Ilex plants. China has abundant germplasm resources of Ilex both in nature and cultivation; more than 200 species have been documented in southwestern China (Chong et al. 2023; Yao et al. 2020). Traditional cross breeding is the main way to create new holly cultivars. ‘Ning Qing 3’ was selected and released from the holly breeding program of Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Memorial Sun Yat-Sen). Its moderate-olivaceous (RHS 146A) (Royal Horticultural Society 2015), shiny, leathery, and oblong leaves have sparked a lot of interest, enriching the Ilex germplasm resources, and significantly improving their ornamental values. ‘Ning Qing 3’ has excellent ecological characteristics, including cold resistance, wide adaptability, pruning resistance, and fewer diseases and pests. Therefore, the cultivar is the ideal tree species for afforestation and landscaping.

Keywords

• hybridization
• leaf character
• ornamental plant