牛樟的组织培养和植株再生

Tissue culture and plant regeneration of Cinnamomum kanehirae Hay

以牛樟侧枝茎段为外植体，建立了牛樟高效离体再生体系，研究取材季节、消毒方式、不同激素配比等因素对茎段再生的影响。结果表明：牛樟外植体采集最佳季节为春夏两季，此时采集的外植体其污染率与褐化率均较低，且出芽快、出芽率高。依次用1000倍甲基托布津处理10 min、75％酒精消毒30 s和0．1％ HgCl2消毒8～10 min的消毒方式能明显降低牛樟外植体的污染率，且对外植体伤害较小。 MS培养基为牛樟生长最适基本培养基，牛樟外植体诱导的最佳培养基为MS ＋6－BA （1．0 mg／L）＋IBA （0.1 mg／L），芽诱导率高且芽体粗壮；丛芽增殖的最佳培养基为MS ＋6－BA （1．5 mg／L）＋ IBA （0.1 mg／L），丛芽增殖率高且芽体健壮；生根培养的最佳培养基为1／2MS ＋ABT（0．2 mg／L）＋ IBA （0．05 mg／L）＋活性炭（0．5 g／L），30 d后生根率可达100％且根系状态较好。

In order to establish a high efficient regeneration system of Cinnamomum kanehirae, its stems were used as explants to study the effects of collection season, sterilization methods and different hormone concentrations on stem regeneration in the processes of buds induction. The results were as follows：The lower infecting and browning rate, quicker differentiation speed and higher germination rate were observed when explants were collected in spring and summer. The infectious rate significantly decreased if the explants were treated by thiophanate-methyl solution diluted 1 000 times for 10 min, 75% alcohol for 30 s and 0.1% mercuric chloride for 8-10 min. And these treatments were harmless to explants. MS was an optimal basic medium. The optimum medium for buds induction was MS＋1.0 mg/L 6-BA＋ 0.1 mg/L IBA, which exhibited higher bud induction rate and thicker buds. MS＋ 1.5 mg/L 6-BA＋ 0.1 mg/L IBA was the optimal medium for bud subculture proliferation, which exhibited higher cluster bud proliferation rate and strong bud. 1/2MS ＋0.2 mg/L ABT＋ 0.05 mg/L IBA＋0.5 g/L AC was the optimal medium for root differentiation, with the rooting percentage 100% after 30 days. Establishment of stable plant regeneration system of C. kanehirae will be useful for saving the resources of endangered species and expanding its living space. Also, it will lay a foundation for the improvement of breeding and the genetic transformation system in the future.