掌叶大黄种子特性研究及无菌培养体系的构建c

目的 研究掌叶大黄种子形态和发芽特性并构建无菌苗和愈伤组织培养体系,为其快繁和次生代谢调控研究提供基础。方法 从大小、净度、千粒质量、生活力、发芽率及发芽势等方面进行10批掌叶大黄种子特性分析;利用正交试验筛选大黄无菌苗建立的消毒体系及愈伤组织诱导的激素配比;HPLC法分析无菌苗和愈伤组织中10种有效成分的含量。结果 10批不同产地来源掌叶大黄的果实及种子外观形态无显著差异,含水量、生活力、发芽率及发芽势有明显差异,和政县与渭源县大黄发芽特性最高;75%乙醇30 s、10% H₂O₂ 15 min为大黄种子无菌苗建立的最佳消毒组合;愈伤组织诱导最佳激素为6-苄氨基腺嘌呤（1.0 mg/L）+6-糠氨基嘌呤（2.0 mg/L）+1-萘乙酸（1.5 mg/L）;不同消毒剂处理种子对无菌苗10种成分的积累无显著影响（P>0.05）,愈伤组织可检测出7种有效成分,含量显著低于无菌苗,大黄酚-8-O-葡萄糖苷含量较其他成分高。结论 以千粒质量、生活力、发芽率及发芽势等指标明确甘肃和政县与渭源县种子特性优良,成功建立掌叶大黄无菌苗与愈伤组织培养体系,为掌叶大黄下一步研究奠定基础。

Investigation on seeds characteristics and establishment of aseptic cultural system for Rheum palmatum

Objective To study the seeds shapes and germination characteristics, construct aseptic seedlings and callus cultural system, and provide a basis for the rapid propagation and secondary metabolic regulation of Rheum palmatum. Methods Ten batches of R. palmatum seeds were subjected to characteristic analyses from the aspects of size, purification, weights per thousand seeds, seeds vigor, germination rates, and germination energy. The optimum disinfection system for aseptic seedlings and the optimum hormone ratio for inducing callus were screened by orthogonal test. The content of ten active components in aseptic seedlings and calli were primarily evaluated by HPLC analysis. Results There was no significant difference in the appearances of the ten batches of R. palmatum seeds from different regions. The content of moisture, seeds vigor, germination rates, and germination energy differed apparently. The germination characteristics in Hezheng and Weiyuan counties were the best. The best disinfection group for aseptic seedlings was the combination of 75% ethanol for 30 s with 10% hydrogen peroxide for 15 min. The optimum hormones for callus induction were 6-BA (1.0 mg/L) + KT (2.0 mg/L) + NAA (1.5 mg/L). Seeds treated with different disinfectants had no significant effect on the content of ten components in germinated aseptic seedlings (P > 0.05). Seven active components were detected in callus, which was significantly lower than that in aseptic seedlings. And the content of chrysophanol-8-O-glucoside was the highest in the callus. Conclusion The seed characteristics from Hezheng and Weiyuan counties in Gansu Province were excellent by analyses of weights per thousand seeds, seeds vigor, germination rates, and germination energy. The aseptic seedlings and callus cultural system of R. palmatum were successfully established, laying a solid foundation for further study.