羊踯躅离体叶片再生体系的建立

Establishment of in vitro Leaf Regeneration System of Rhododendron molle (Blume) G.Don

为了建立羊踯躅规模化无性繁殖和高效遗传转化体系,以羊踯躅试管苗叶片为外植体,探讨了基本培养基类型、叶片切割方式、叶位、暗培养时间及不同激素组合等因素对叶片再生不定芽的影响。结果表明:WPM培养基为最适基本培养基。垂直于主脉切割一刀并去除叶柄和叶稍的叶片再生不定芽的频率最高。羊踯躅试管苗中、上部叶片的再生能力较强,其中第5和第6位叶的不定芽诱导效果最佳。初始暗培养有利于叶片再生,暗培养10~15天的效果最佳。诱导羊踯躅试管苗叶片再生不定芽的适宜培养基为WPM+TDZ 1.0 mg/L+IAA 1.0 mg/L,其不定芽分化率和平均分化芽数分别达到82.3%和7.2个。

To establish a system for large-scale vegetative propagation and efficient genetic transformation of Rhododendron molle, the leaves of Rhododendron moUe plantlets in vitro were used as explants, the effects of basic medium type, leaf cutting mode, leaf position, darkness culture time and different hormone combinations on the adventitious bud regeneration of leaves were studied. The results showed that WPM medium was the optimal basic culture medium. The regeneration frequency of adventitious buds was the highest in the leaves which were cut perpendicularly in the main veins and the petioles and leaf apexes were removed. The regeneration ability of leaves at middle and upper parts of a plantlet was stronger, and the induction effect of adventitious bud from leaves at the 5th and 6th positions was the best. The initial dark culture was beneficial to regeneration of leaves and the optimal time of dark culture was 10-15 d. The optimum medium for adventitious bud regeneration was WPM＋TDZ 1.0 mg/L＋ IAA 1.0 mg/L and the regeneration frequency was 82.3% and the average number of adventitious bud was 7.2.