Abstract

Vaccinium bracteatum Thunb. is a vigorous plant that is easy to grow, can adapt to various acid soil species and has good resistance to drought. It has fewer pest problems than most other blueberry cultivars, offering an advantage rootstock for various blueberry cultivars to resist pest and disease. However, it is relatively difficult to propagate and the cuttings can be difficult to root. The present study is an investigation into the effects of the types and combination of plant growth regulators on the tissue culture system of V. bracteatum Thunb. When nodal explants were cultured on media without plant growth regulators (PGRs), the shoots did not produce new buds, while all media supplemented with PGRs significantly affected adventitious bud proliferation in woody plant medium (WPM). Upon addition of PGRs, adventitious buds occurred and significant differences were observed (P < 0.05). The shoot length and proliferation coefficient in WPM basal medium containing 0 mg L^-1 KT, 2.0 mg L^-1BA, 2.0 mg L^-1 ZT and 2.0 mg L^-1 TDZ was much more than other concentrations. The shoot length and proliferation reached 9.64 and 7.66 cm. For rooting, significant variation was observed (P < 0.05) between different concentrations of IBA and NAA. In general, the effect of IBA was much better than NAA. The root length gradually increased with increasing concentration of IBA from 0 to 2.0 mg L^-1 followed by a decrease from 2.0 to 4.0 mg L^-1. The highest root length and number was 3.16 and 3.33 cm respectively when the concentration of IBA was 2.0 mg L^-1.

Key words: Vaccinium bracteatum Thunb., plant growth regulator, tissue culture, micropropagation.