Yujie Yang, Zhihui Li, Xiaoling Jin, Donglin Zhang , Jinying Dong
Holly (Ilex) is a large genus in Aquifoliaceae, which is comprises of 400 to 600 deciduous and evergreen species. This genus is cultivated as important medicinal and ornamental plants in the temperate and subtropical regions (Galle, 1997; Hu, 1989). The great diversity and adaptability of hollies make them as the king in gardens and landscapes. They can be used as shade trees, dividing lines, hedges, and groundcovers. They have beautiful effects of fruits in autumn, masses of evergreen foliage, and bright glistening color of variegated cultivars (Robinson, 1984). Ilex crenata Thunb. is native to eastern China, Japan, Korea, Kuril, Sakhalin, Philippines, and the Himalayas. Now it is widely planted as an ornamental plant in the southeastern US for its dense evergreen foliage and various forms (Dirr, 2009). Many cultivars have been released for commercial production such as I. crenata (Fastigiata Group) ‘Sky Pencil’, which is popular in the landscape for its strongly upright habit and lustrous, dark evergreen foliage (Dirr, 2011).
Similar to the majority of Ilex species, seed germination of ‘Sky Pencil’ is inefficient as a result of low germination rate and long germination time. It usually takes 2 to 3 years to overcome the double dormancy from hard, impermeable seed coat and immature embryos (Dirr and Heuser, 2006). Normally, ‘Sky Pencil’ is propagated by rooting of stem cuttings with 1000-3000 ppm IBA (The United States National Arboretum). But for plant breeders, it is hard to select new cultivar from cuttings. New cultivars are from open pollinated and artificial cross. Therefore, seed germination is the key point to select new cultivars from I. crenata ‘Sky Pencil’. To shorten the germination time and select new cultivars efficiently, we investigated the embryo germination of I. crenata ‘Sky Pencil’.
Yujie Yang, , Zhihui Li, , Xiaoling Jin, , Donglin Zhang , and Jinying Dong, (2015). ILEX EMBRYO GERMINATION SAVING YOUR TIME©. Acta Hortic. 1085, 493-497
DOI: 10.17660/ActaHortic.2015.1085.100

Acta Horticulturae