白花泡桐同源四倍体的诱导

将预培养不同时间的白花泡桐组培苗叶片分别放置到含有不同浓度秋水仙素的双层(液体和固体)MS NAA 0.1 mg·L-1 BA 18 mg·L-1培养基上进行染色体加倍试验,通过根尖染色体计数和叶片单细胞相对DNA含量测定进行变异植株的倍性分析.结果表明:秋水仙素浓度对叶片存活率和芽诱导的影响达到极显著水平,对四倍体诱导的影响不显著;秋水仙素处理外植体时间对四倍体诱导率影响显著,外植体预培养时间对芽诱导率和四倍体诱导率的影响达到极显著水平.在9个试验组合中,用5 mg·L-1秋水仙素处理预培养12 d白花泡桐叶片72 h时,四倍体诱导率最高可达20.0%.诱导出的四倍体植株叶片较二倍体增大、增厚,叶片单个气孔器变大,叶片气孔密度变小.

Induction of Autotetraploid of Paulownia fortunei

Induction of autotetraploidy Paulownia forunei from the pre-cultured leaves of the diploid with different concentrations of colchicines on the double (liquid and solid) media MS NAA 0.1 mg\5L -1 BA 18 mg\5L -1 through chromosome numbering of the plant tip cells was conducted, and DNA content in leaf cell were investigated. The results indicated that a more significant difference of explant survival and shoot induction rates and non-significant difference of tetraploid induction rate occurred among various treatments with colchicines, a significant difference of tetraploid induction rate occurred within the treatment time of explants with colchicines, and a more significant difference of shoot and tetraploid induction rates occurred for the time of explants precultured. The tetraploid induction rate might reach 20.0% from the explants pre-cultured for 12 d and treated with 5 mg\5L -1colchicine for 72 h on the double media among the nine experiments. Moreover, leaves of the tetraploid seedlings were larger and thicker than those of the diploid ones, and the stomatal size and density on the leaf larger and thicker than those of the diploid respectively.