麻栎茎段体胚发生和组织学观察初报

分别于2010年4月和6月采集同一麻栎母株的成熟茎段，在培养基MS+6-BA 1 mg·L^-1+IBA 1 mg·L^-1+谷氨酰胺1 000 mg·L^-1+脯氨酸500 mg·L^-1上诱导体胚发生，选出较好的外植体采集时间。通过组织学和扫描电镜观察，研究麻栎体胚的起源和愈伤组织结构特征。结果表明，外植体较好的采集时间为4月。组织切片表明，麻栎体胚具有三种不同的起源方式，起源于愈伤组织内部、表皮或者初生胚性复合体表面；胚性愈伤组织的细胞较小，细胞质浓厚，染色较深，和非胚性组织细胞明显不同。扫描电镜(SEM)观察表明，胚性愈伤组织细胞呈球形，大小均一，多以细胞团形式存在；非胚性愈伤组织细胞无规则形状，细胞间隙较多，大多分散存在，这些可以作为区分两类愈伤组织的典型特征。

Preliminary Report on Somatic Embryogenesis from Stem of Quercus acutissima Carr. and Histological Observation

The explants were collected in April and June from the same mother plant. The medium MS+6-BA 1 mg·L^-1+IBA 1 mg·L^-1 supplemented with L-glutamine 1 000 mg·L^-1 and proline 500 mg·L^-1 was used for somatic embryogenesis. The results showed that the better acquisition time is April. The histological study revealed that the cells of embryonic were small in size and dense in cytoplasm, which were significantly different with the cells of non-embryonic callus. The histological origin of somatic embryos was internal callus, subepidermal cells or surface of primary embryogenic complex. Observations by scanning electron microscopy (SEM) showed that the structure differences between embryogenic and non-embryogenic callus were distinct. We found that the cells of embryogenic callus were equal in size and had the shape of ball. There were cell masses consisting of many embrgogenic cells. The cells of non-embryogenic callus had no regular shape. There was interspace between them and cannot form cell masses.