[Optimization of noni callus induction and establishment of callus suspension system].

The aim of the study was to obtain the secondary metabolites in the stem segment of noni and to establish genetic transformation system. The stem segments (no axillary buds) of noni were used as explants to induce the callus, and then to establish the cell suspension system. The factors affecting callus induction and cell suspension were studied. The results showed that the optimal culture medium for induction was MS with 1.0 mg/L 6-Benzylaminopurine (6-BA) and 0.1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), and the optimum culture medium for suspension was MS with 1.0 mg/L 6-BA and 0.1 mg/L 2,4-D, 3% sucrose and the pH of 5.85, with the initial inoculation amount of 37.5 g/L, and the speed of 110 r/min and 25±2 °C applying darkness culture. The suspension cells grew well and showed the maximum growth rate. The growth curve of the suspension cells from the stem segment of noni was in "S-typed" trend, and it should be transformed to the fresh medium between 12 and 20 d. During the culture, the pH of the culture medium decreased and then slowly increased, and the optimum pH for the suspension cells culture of callus from noni's stem segments was 4.5-5.0. In this study, the stable cell suspension system of the stem segment of noni was successfully established.为获取诺丽茎段中的次生代谢物并为建立遗传转化体系奠定基础，以诺丽茎段(无腋芽)为外植体诱导愈伤组织，并建立细胞悬浮系，对影响愈伤组织的诱导及细胞悬浮系的因子进行了研究。结果表明：愈伤组织诱导的最优培养基是MS+1.0 mg/L 6-BA+0.1 mg/L 2,4-D；悬浮培养的最佳培养基为MS+1.0 mg/L 6-BA+0.1 mg/L 2,4-D+3%蔗糖，pH 为 5.85，当初始接种量为 37.5 g/L、摇床转速为 110 r/min 且 (25±2)℃ 暗培养时，悬浮细胞生长良好，生长速率最大；诺丽茎段悬浮细胞生长曲线呈“S”型，最适继代周期为12–20 d；培养过程中，培养基的pH 呈先下降后缓慢升高的变化趋势，诺丽茎段愈伤组织悬浮细胞培养的最适pH 在4.5–5.0 之间。文中成功建立了以诺丽茎段为外植体的稳定的细胞悬浮系。.