Propagation of Ornamental Plants
18(4): 109-114, 2018
IN VITRO REGENERATION OF EVERGREEN DOGWOODS FROM EAST ASIA GROUP VIA ADVENTITIOUS SHOOTS ORGANOGENESIS
Yang Zhang1, Xun Yang1, Xiu-Li Lv2, and Xiang-Xiang Fu1*
1 Southern Modern Forestry Collaborative Innovation Centre, College of Forestry, Nanjing Forestry University, 159 Lonpan road, 210037 Nanjing, China, *Fax: + 86 025085427402, *E-mail: xxfu@njfu.edu.cn 2 Shanghai Academy of Landscape Architecture Science and Planning, 200232 Shanghai, China
Cornus hongkongensis subsp. tonkinensis and C. elliptica are important evergreen dogwoods as resources for cultivar selection and breeding, as well as good rootstocks for cultivars from North America group. To meet the expanding horticultural needs, in vitro propagation systems for these two dogwoods were established via adventitious shoots induction. C. hongkongensis subsp. tonkinensis was disinfected with 70% ethanol (30 s) and 0.1% (w/v) mercuric chloride (HgCl2) (7 min), obtaining contamination rate of 12.9 ± 1.5% and survival rate of 92.8 ± 1.9% for explants sampled from 5-year old saplings during April-May (A-M). Maximum response for induction frequency (77.8 ± 0.0%), mean number of shoots (3.7 ± 0.0), and rooting rate (52.4 ± 1.4%) achieved on woody plant media (WPM) with 1.5 mg l-1 6-benzylaminopurine (BAP) + 0.05 mg l-1 α-naphthaleneacetic acid (NAA), 0.02 mg l-1 thidiazuron (TDZ) + 0.1 mg l-1 NAA and 0.02 mg l-1 TDZ + 0.1 mg l-1 NAA, respectively. C. elliptica was disinfected with 70% ethanol (15 s), two drops of tween 80 and 3% (w/v) sodium hypochlorite (NaClO) (15 min), getting contamination rate of 4.6 ± 0.1% and survival rate of 86.6 ± 1.2% for explants from 1-year old seedlings. Maximum response for induction frequency (85.9 ± 0.5%), multiplied shoots (4.0 ± 0.1), and rooting rate (88.9 ± 7.8%) achieved on WPM with 1.0 mg l-1 BAP + 0.05 mg l-1 kinetin (KT) + 0.1 mg l-1 NAA, 1.0 mg l-1 BAP + 0.2 mg l-1 NAA and 1.0 mg l-1 indole-3-butyric acid (IBA), respectively. The elaborated regeneration systems could motivate efforts involving introduction, popularization, and application of dogwood cultivars.
Key words: Cornus, sampling time, disinfection, PGRs (plant growth regulators), tissue culture
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