三种桃砧木的离体快繁技术研究

Micropropagation Technique of Three Peach Rootstocks in vitro

以红花山桃、筑波5号、光核桃茎段为外植体，研究了不同消毒方法、取材时间对外植体萌芽率的影响，不同基本培养基、不同激素种类和浓度对腋芽增殖及生根的影响。外植体消毒和取材时间试验结果表明，3种砧木以75％酒精浸洗30s，0．1％HgCl2＋吐温浸洗7min，清水冲洗6次，外植体萌芽率最高；外植体的取材时间对萌芽率影响较大，红花山桃、筑波5号分别于3—4月份和4～5月取材时，萌芽率较高，而光核桃在3～6月取材时萌发率均无显著差异。增殖培养条件筛选发现：红花山桃和光核桃的最佳增殖培养基类似，在LP＋6-BA1．0mg／L＋IBA0．2mg／L培养条件下增殖系数较高，且试管苗生长健壮；而筑波5号的最佳增殖培养基为MS＋6-BA2．0mg／L＋IBA0．2mg／L；3种砧木在筛选出的培养条件下，均随着继代次数的增加增殖系数增加。生根培养条件筛选发现，红花山桃和光核桃的生根条件为1／2MS＋IAA1．0mg／L＋NAA1．0mg／L，但筑波5号生根困难。

Stems of Honghuashantao,Zhubo 5 and Guanghetao were used as explants in this study. Effects of different sterilization methods and sampling dates of the explants on germination rate in vitro, as well as effects of different basic mediums, kinds and concentration of hormones on buds proliferation and rooting were studied. The results showed as follows：For sterilization, the best process was that explants were washed by 75% alcohol for 30 s firstly, then treated with 0. 1% mercuric chloride and tween for 7 min, lastly washed with sterile wuter for six times. Greatest effects of sampling time on germination rate were fund among the three rootstocks. Higher percentage of bud germination was found when explants of Honghuashantao and Zhubo 5 were sampled from March to April, and April to May respectively. But for Guanghetao, no significant difference of bud germination was found when sampled from March to June. According to the results of proliferation medium selection, similar optimal medium, LP ＋ 6-BA 1.0 mg/L ＋ IBA 0.2 mg/L, for proliferation of Hanghuashantao and Guanghetao was found. While different medium for Zhubo 5, MS ＋ 6-BA 2. 0 mg/L ＋ IBA 0. 2 mg/L, was selected. The shoots could grow healthily and proliferate rapidly on these selected mediums, and more shoots were proliferated when the transplant times of the shoots increased. The rooting medium selected for Honghuashantao and Guanghetao was 1/2 MS ＋ IAA 1.0 mg/L ＋ NAA 1.0 mg/L. No adaptable rooting medium was selected out for Zhubo 5 because of its less rooting ability.