RiT-DNA对四倍体菘蓝的遗传转化及其植株再生

目的：建立一套利用发根农杆菌转化四倍体菘蓝的有效方法。方法：利用发根农杆菌R1601，ASTCC15834和A4感染四倍体菘蓝的子叶外植体诱导出毛状根，再将毛状根置于含不同激素的培养基上诱导再生植株。结果：3种农杆菌具有不同的诱导能力，毛状根在不含激素的MS固体培养基上快速生长并表现出典型的毛根性状：多分枝、多根毛且无向地性，经冠瘿碱分析证明确已被转化。毛状根在无激素的MS增养基中悬浮培养两周后其生物量增加近35倍，在含BA的MS固体培养基上不经愈伤组织阶段直接分化出不定芽，所有不定芽都可在生根培养基上生根长成再生植株。冠瘿碱检测表明Ri质粒的T-DNA部分已转化到再生植株基因组中。结论：发根农杆菌可以诱导四倍体菘蓝长出毛状根，经诱导出的毛状根具有再生完整植株的能力。

Genetic Transformation of Autotetraploid Isatis Indigotica Fort.Induced by Ri T-DNA and Plant Regeneration

Objective: To establish an effective system for genetic transformation of autotetraploid Isatis indigotica by Agrobacterium rhizogenes. Method: Agrobacterium rhizogenes strains R1601,ATCC15834 and A4 were employed to induce hairy roots from autotetraploid Isatis indigotica, and the obtained hairy roots were developed into regenerated plants on solid MS media with different Kinfs of plant grouth regulators. Result: Root induction differed obviously. by three Agrobacterium strains. Hairy roots grew rapidly on solid MS medium without plant growth regulators and showed the typical hairy root phenotype: profuse branching, high density of root hairs and plagiotropism. And the transformation of Ri T-DNA was confirmed by opine analysis. The biomass of hairy roots increased nearly 35 times regulator-free MS after suspended in plant growth two weeks. On solid MS medium with BA, adventitious buds were differentiated directly from hairy roots without callus formation. All of the adventitious buds were rooted on root induction medium and developed into regenerated plants. Opine analysis indicated the integration of Ri T-DNA in the transformed plants. Conclusion: Agrobacterium rhizogene can induce hairy roots from autotetraploid Isatis indigotica, and the obtained hairy roots can develop into regenerated plants.