文心兰类原球茎液体增殖过程中秋水仙素化学诱变

 采用秋水仙素对液体增殖培养中的文心兰类原球茎进行多倍体诱变, 获得了大量的文心兰多倍体试管苗。结果表明, 秋水仙素浓度越高, 处理时间越长, 类原球茎受伤害程度越严重, 再生苗多倍体比例越大, 最高诱变率可达46.7%; 低浓度, 短时间秋水仙素处理易产生嵌合体; 四倍体试管苗植株粗短, 健壮, 叶片宽厚, 叶片下表皮气孔张度较大, 下表皮细胞核较大且靠近细胞壁边缘; 根尖细胞染色体数加倍。

Colchicines Chemical Induction During Propagation of Protocorm-like Bodies of Oncidium in Liquid Culture

Colchicines were employed to induce polyploid plantlets of Oncidium during ropagation of protocorm-like bodies ( PLB s) in liquid culture. A lot of polyploid plantlets were obtained by this technique.The results showed that the PLBs cultured in the medium contained higher concentration of colchicines gotharmed more severely and the rate of ployploid plantlets was bigger with higher concentration of colchicines or longer time of treatment . The biggest rate of polyploid plantlets regenerated from the PLBs could reach to 46.7%. The mixoploid could be produced under the condition of lower concentrations of colchicines and short time of treatment. The tetraloid plantlets were shorter and stronger and leaves changed broad and thick. The diameter of lower epidermal stomata in the tetraploid was a little bigger than the one in the diploid. The cell nucleus of leaf lower epidermal became bigger and approached to cell wall. The number of chromosomes in root tip cells of the polyploid plantlets were doubled.