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为建立黑木相思(Acacia melanoxylon R.Br.)茎段高频率再生体系,以优良无性系(SR17)组培苗茎段为外植体,研究培养基中添加TDZ及TDZ与IAA组合使用、不同浓度Ag NO3以及茎段部位对愈伤组织诱导和不定芽再生的影响.结果表明:当TDZ质量浓度为0.05 mg/L时,愈伤诱导率、不定芽分化率和不定芽数最高,IAA 0.05 mg/L配合TDZ使用可使不定芽分化率高达89.4％.同时发现不同质量浓度Ag NO3对不定芽分化率影响不显著,当Ag NO3＞2.5 mg/L时,诱导的愈伤和不定芽容易产生玻璃化.另外发现组培苗中部茎段最有利于不定芽分化.因此选择组培苗中部茎段为外植体,在WPM+TDZ 0.05 mg/L+IAA 0.05 mg/L的诱导培养基上培养30 d,转入MS+6BA 0.5 mg/L+IBA 0.5 mg/L的分化培养基上培养30 d获得最高的不定芽诱导率,且平均每个外植体形成14.3个不定芽.将经过伸长生长的不定芽转入生根培养基1/2 MS+IAA 2.0 mg/L+IBA 0.5 mg/L时,生根率高达95.8％.生根培养10 d,炼苗培养20 d后获得可供移植的组培苗.本研究为黑木相思遗传转化和分子育种提供理论参考.“,”To established an efficient regeneration system for the stem of blackwood (Acacia melanoxylon), the stems segments of tissue culture seedlings from blackwood superior clone SR17 were used as explants. The effects of TDZ, the combination of TDZ and IAA, different concentrations of Ag NO3 and stem segments on callus induction and adventitious bud regeneration were studied. The results showed that callus induction rate, adventitious buds induction rate and the number of adventitious buds induction were highest in medium with0.05 mg/L TDZ. It was also found that the rate of adventitious bud differentiation could reach as high as 89.4％when the stem was cultured in a modified woody plant medium (WPM) supplemented with 0.05 mg/L TDZ and0.05 mg/L IAA. At the same time, we found that Ag NO3 could not significantly affect the blackwood adventitious buds induction, and the induced callus and adventitious buds are easy to produce vitrification when medium contained more than 2.5 mg/L Ag NO3. Additionally, the middle segment of stem was prior to inducting adventitious buds. Thus, the middle segment of stem from tissue culture seedlings were used as explant and cultured in modified WPM medium, supplemented with 0.05 mg/L TDZ and 0.05 mg/L IAA for 30 d, and then transferred to MS medium, supplemented with 0.5 mg/L BAP and 0.5 mg/L IBA for 30 d. The highest adventitious buds induction rate was obtained, and the number of buds per explant reached 14.3. When the elongated adventitious bud was transferred to the rooting medium 1/2 MS+IAA 2 mg/L+IBA 0.5 mg/L, the rooting rate was as high as95.8％. After rooting culture for 10 d and hardening-seedling for 20 d, tissue culture seedlings for transplantation were obtained. This study could provide theoretical reference for genetic transformation and molecular breeding of Acacia melanoxylon.