不同激素浓度配比对竹叶石斛种子快繁的影响

摘要

以竹叶石斛(Dendrobium hancockii Rolfe)的成熟种子为实验材料,以1/2MS为基本培养基,研究了不同浓度激素配比对竹叶石斛的原球茎增殖分化和生根壮苗培养的影响,以期建立竹叶石斛的种子快繁技术,结果表明:竹叶石斛成熟种子在1/2MS萌发培养基中,45 d即可出现大量原球茎,种子萌发率高达95％;在原球茎分化阶段,最佳培养基为1/2MS+6-BA 2.0 mg/L+NAA 0.2 mg/L+蔗糖30 g/L+琼脂7 g/L,pH 5.8,50 d左右即可分化成小植株;在生根壮苗培养阶段,最佳生根培养基为1/2MS+NAA 0.7 mg/L+蔗糖30 g/L+琼脂7 g/L,pH 5.8,45 d左右组培苗长到3 cm以上,根的条数为2条以上,叶2片以上.利用组织培养技术进行竹叶石斛种子快速繁殖,以1/2MS为基本培养,从种子萌发到无菌苗生根并达到炼苗移栽要求所需的时间在150 d以内,这大大加快了竹叶石斛种子繁殖速度,为竹叶石斛的快速生产提供了便利.%Using the mature seeds of Dendrobium hancockii Rolfe as experimental materials,taking 1/2MS as basic culture medium,we studied the effects of different concentrations of hormone combinations on the differentiation,propagation and rooting of D.hancockii protocorms,in order to establish a rapid seed propagation technique system.The results showed that it just needed 45 days to appear a large number of protocorms when the mature seeds of D.hancockii germinated in 1/2MS medium,and the rate of seed germination reached 95％.In protocorm differentiation phase,the best medium was 1/2MS+6-BA 2.0 mg/L+NAA 0.2 mg/L+ sucrose 30 g/L+ agar 7 g/L (pH 5.8),and it needed only about 50 days for protocorm to differentiate into plantlets.The best rooting medium was 1/2MS+NAA 0.7 mg/L+ sucrose 30 g/L+ agar 7 g/L (pH 5.8);after rooting culture for 45 days or so,the plantlets grew to 3 cm,the number of roots exceeded 2,and the number of leaves was more than 2.When the seeds of D.hancockii were propagated under the above optimum culture medium conditions,the duration from germination of seeds to formation of healthy and strong plantlets was within 150 days,which could provide convenience for the rapid production of D.hancockii.