大字杜鹃离体快繁体系建立及种质试管保存研究

以大字杜鹃新生嫩芽为外植体，应用均匀设计法筛选其最适合的嫩芽基部直接再生芽苗、生根及种质试管保存的培养基，结果表明，最适合的基部直接再生芽苗诱导培养基为：DR+2-ip3.00 mg·L^-1，诱导率达95.5%以上；生根培养基：MS(改良)+IAA 0.50 mg·L^-1+IBA 0.10 mg·L^-1+KT 0.10 mg·L^-1，生根率达99%以上；试管保存培养基：N-68+B₉ 2.30 mg·L^-1+根皮苷1.50 mg·L^-1，保存时间可达30个月以上。以再生植株的茎节为材料进行快繁的结果表明，在28 d的一个培养周期内增殖倍数平均达65以上。常温条件下，采取“矮化延缓生长”的方法在试管内保存种质资源，建立了大字杜鹃的离体培养和种质试管保存体系。

In Vitro Rapid Propagation System and in Vitro Germplasm Peservation of Rhododendron schlippenbachii Maxim.

The tender buds of Rhododendron schlippenbachii Maxim. were used as explants in the experiment. Uniform Design was used-for screening the most suitable culture medium for shoots regeneration immediately at base of tender buds, rooting and in vitro germplasm preservation. The results showed that DR+2-ip3.00 mg·L^-1 was the most suitable for shoots regeneration, the rate of regeneration was more than 95.5%; MS(modified)+IAA0.50 mg·L^-1+IBA0.10 mg·L^-1+KT0.10 mg·L^-1 for rooting, the rate of rooting was more than 99%; N-68+B₉ 2.30 mg·L^-1+phloridzin 1.50 mg·L^-1 for germplasm preservation in vitro for 30 months. Stems each with one node were cut from regenerated shoots and cultured for propagation, and a 65-fold proliferation rate was achieved within 28 days. The method of “defering growth with dwarfing” was utilized for in vitro germplasm peservation at normal temperature. In vitro culture and in vitro germplasm peservation system of R. schlippenbachii Maxim. has been successfully established.