碳源对早花百子莲愈伤组织诱导及其增殖的生理特性影响

为揭示碳源对早花百子莲愈伤组织诱导与增殖的影响机理,该研究以早花百子莲的小花梗为外植体,比较分析30.0 g/L蔗糖、葡萄糖、麦芽糖在愈伤组织诱导、增殖中的效果,测定不同碳源种类处理下愈伤组织增殖相关生理特性,并根据细胞增殖效果、生理指标相关性进行优化验证。结果表明:(1)蔗糖、葡萄糖和麦芽糖碳源处理下,愈伤组织诱导率分别为86.00%、72.00%和59.67%,蔗糖碳源的愈伤组织诱导率比葡萄糖和麦芽糖分别显著提高19.44%和44.13%(P<0.05),蔗糖碳源较葡萄糖和麦芽糖碳源的愈伤组织大小分别显著增加22.44%和90.09%(P<0.05);愈伤组织增殖阶段,蔗糖碳源能够同时维持良好的细胞增殖效率及活性,而葡萄糖碳源的愈伤组织增殖快、状态差,麦芽糖处理增殖慢、状态佳;蔗糖转换葡萄糖碳源后愈伤组织细胞团大小、细胞活性明显下降;蔗糖转换蔗糖、蔗糖转换麦芽糖的效果较好。(2)培养基碳源显著调节愈伤组织增殖阶段的糖代谢、内源激素代谢和氧化胁迫平衡。(3)愈伤组织的主要糖组分为淀粉、葡萄糖;淀粉、麦芽糖含量与细胞团大小相关性高,以蔗糖为碳源的培养基中添加麦芽糖,愈伤组织...

Influence on Callus Induction and Physiological Characters of Callus Proliferation in Agapanthus praecox ssp. orientalis by Carbon Sources

To reveal the effects of carbon sources on callus induction and proliferation, we studied comparative analyses of 30.0 g/L sucrose, glucose and maltose on callus induction and proliferation by using pedicel as explants in Agapanthus praecox ssp. orientalis. Physiological indicators of callus proliferation stage were determined, and the correlation coefficients of cell proliferation and physiological indexes were evaluated. Furthermore, the effectiveness of some physiological indicators on callus proliferation was confirmed. Here are the results. (1) The callus induction rate was 86.00%, 72.00% and 59.67% with sucrose, glucose and maltose treatment, respectively. The callus induction rate of sucrose treatment significantly increased by 19.44% and 44.13% compared with glucose and maltose respectively (P < 0.05). Meanwhile, the callus size of sucrose treatment significantly increased by 22.44% and 90.09% compared with glucose and maltose respectively (P < 0.05). In callus proliferation stage, sucrose can maintain both proliferation efficiency and cell viability. However, glucose treatment induced higher cell proliferation rate and poor cell viability, and maltose treatment induced slow cell proliferation rate and vigorous cell viability. Carbon sources conversion treatment indicated that callus cell mass size and cell state decreased sharply, when callus transferred from sucrose to glucose medium. However, the proliferation efficiencies of both from sucrose to sucrose and from sucrose to maltose were well. (2) Carbon sources significantly regulated sugar metabolism, endogenous hormone metabolism and oxidative stress balance in the process of callus proliferation. (3) Starch and glucose were the principal saccharides components of callus, and the contents of starch and maltose were highly correlated with cell mass proliferation efficiency. The combination of sucrose and maltose optimized callus proliferation, the cell mass color was bright yellow, and cell activity was vigorous. (4) Contents of binding IAA, GA₄, and CTK were correlated with callus cell mass size. The addition of 1.0 mg·L^-1 6 BA considerably promoted cell proliferation efficiency (P < 0.05). (5) ROS activity was negatively correlated with POD and CAT activities, and POD activity was negatively correlated with H₂O₂ content (P < 0.05). The POD and CAT activities were extremely significant positive correlated (P < 0.01). (6) The results of validation and optimization experiments showed that the addition of maltose and 6 BA in the culture medium effectively promoted callus proliferation in A. praecox, in which maltose maintained and improved the cell activity, while 6 BA mainly promoted cell proliferation. In conclusion, sucrose was the most appropriate carbon source for callus induction and proliferation in A. praecox. Sucrose and maltose combination improved cell viability, while picloram and 6 BA combination accelerated callus proliferation. The optimized medium for callus proliferation was MS + 0.5 mg/L PIC + 1.5 mg/L 6 BA + 15.0 g/L sucrose +15.0 g/L maltose + 7.0 g/L agar.