银白杨叶片不定芽再生影响因素的研究

Establishment of high frequency regeneration system of adventitious bud from leaves of Populus alba

该文以银白杨无菌试管苗叶片为外植体 ,进行了不同培养基及不同因子对银白杨叶片不定芽诱导的研究 ,建立了叶片不定芽再生植株体系 ,为今后的遗传工程改良奠定了基础 .结果表明 :银白杨叶片不定芽诱导的最适培养基是MS附加 6 BA和NAA(5∶1) (即MS +6 BA 0 5mg L +NAA 0 1mg L +蔗糖 2 5 % +琼脂 0 5 5 % ,pH 5 8) ,不定芽再生率达 95 %以上 ;当 6 BA NAA <5时 ,叶片不定芽再生率和再生系数均降低 ,当 5≤ 6 BA NAA≤ 30时 ,随着比值的增大 ,不定芽再生率明显下降 ,不定芽再生系数也减少 ;叶片不定芽再生能力强的最佳取材位置是自试管苗顶端向下伸展叶的第 1～ 3片叶 ;生根试管植株叶片的不定芽再生能力强于无根试管植株 ;叶片不定芽诱导的最佳光照时间为每天 14h .

Adventitious bud regeneration from leaves of Populus alba in vitro with different media and factors of tissue culture is studied.Some procedures on rapid propagation of leaf explants are established. And it is better for future transformation of Populus alba. The results indicate that the optimal medium for adventitious bud regeneration is MS medium supplemented with 6--BA and NAA(5∶1) (MS+6--BA 0.5 mg/L+NAA 0.1 mg/L+Sugar 2.5%+agar 0.55%),and the frequency of adventitious bud regeneration is more than 95%; When the ratio is below 5∶1,both the frequency of adventitious bud regeneration and the coefficient of bud regeneration slows down. When the ratio is between 5 and 30, the frequency of adventitious bud regeneration slows down apparently and the coefficient of bud regeneration also decreases with the increase of the ratio;The best leaves for adventitious bud regeneration are the first three top leaves of a shoot.The leaf explants of rooted tube plants are more propitious to induce adventitious buds than those of non-rooted tube plants.The differentiation rate of adventitious bud is higher under 14 h illumination per day than others.