【摘要】 【目的】山苍子是我国重要的木本油料树种，为突破其传统繁育技术瓶颈，研究旨在建立高效的山苍子体胚发生体系，为实现规模化繁殖提供技术支撑。【方法】以5—8月的山苍子种胚为外植体，设置7个采集时间处理，通过单因素和正交试验等方法，探究采集时间、高浓度蔗糖浸泡、活性炭浓度、有机营养及激素（6-BA、2,4-D和IAA）对体胚发生和次生胚增殖的影响，从而确定山苍子体胚发生及其次生胚增殖较适宜的培养基及其培养条件。【结果】体胚发生阶段在（24±2）℃黑暗环境下培养90 d，结果表明：山苍子种胚可通过直接或间接途径形成体细胞胚；种胚最佳采集时间为盛花期后75 d，此时的种子表现出适当的分化能力和抗逆性，具有较高的体胚发生潜力；培养基中添加一定浓度的活性炭可提高体胚发生率，150 mg/L为其适宜浓度，超过此浓度将对体胚发生产生抑制作用；对不同浓度6-BA(0.5,1.0,1.5,2.0 mg/L)、2,4-D(0.2,0.4,0.6,0.8 mg/L)与IAA(0.25,0.5,0.75,1.0 mg/L)进行三因素四水平的正交试验，极差分析表明：在不考虑交互作用的情况下，因子主次顺序依次为IAA、6-BA和2,4-D，筛选出促进山苍子体胚诱导的最佳培养基为MS+30 g/L蔗糖+7.0 g/L琼脂+700 mg/L水解酪蛋白+2 mg/L 6-BA+0.6 mg/L 2,4-D+0.5 mg/L IAA，其体胚发生率最高可达23.3%。次生胚增殖阶段在（24±2）℃黑暗环境下培养30 d，结果表明：6-BA(P<0.01)和NAA(P<0.05)对次生胚增殖的影响最为显著，最佳增殖培养基为MS+30 g/L蔗糖+7.0 g/L琼脂+700 mg/L水解酪蛋白+0.1 mg/L 6-BA+0.5 mg/L NAA+600 mg/L肌醇+200 mg/L环糊精，最高增殖倍数达20.17倍。【结论】研究显著提高了山苍子体胚发生率及次生胚增殖效率，为山苍子规模化繁殖提供了技术支撑。更多还原

【Abstract】 [Objective]As an economically important woody oilseed species in China,Litsea cubeba(Lour.)Pers. faces significant bottlenecks in conventional propagation methods.This study aims to establish an efficient somatic embryogenesis system for L. cubeba to achieve mass propagation,thereby overcoming the limitations of traditional breeding techniques characterized by long cycles and low multiplication rates.[Method]Somatic embryogenesis stage:The single factor experimental method was used to explore the effect of activated carbon concentration on somatic embryogenesis,and the embryos of L. cubeba from May to August were used as explants,and 7 collection times were set to explore the effects of different collection times on somatic embryogenesis. In this study,the effects of high-concentration sucrose solution immersion,sucrose and acid hydrolyzed casein content on somatic embryogenesis were investigated by three-factor and three-level orthogonal experiments.Besides,the effects of different concentrations of 6-BA,2,4-D and IAA on somatic embryogenesis were investigated by using a three-factor and four-level orthogonal experimental method.Secondary embryo proliferation stage:The effects of different concentrations of 6-BA,NAA,inositol and cyclodextrin on the proliferation of secondary embryos were investigated by a four-factor three-level experimental method. In this way,the most suitable medium and culture conditions for the somatic embryogenesis and secondary embryogenesis of L. cubeba and its secondary embryonic proliferation were determined.[Result]During somatic embryogenesis(cultured at 24±2 ℃ in darkness for 90 days),embryos developed through direct or indirect pathways.The optimal collection time was 75 days after full bloom,when seeds exhibited appropriate differentiation and stress resistance with high embryogenic potential. Activated charcoal at 150 mg/L showed the best effect,while higher concentrations inhibited embryogenesis.Orthogonal tests with three factors6-BA(0.5,1.0,1.5,and 2.0 mg/L),2,4-D(0.2,0.4,0.6,and 0.8 mg/L),and IAA(0.25,0.5,0.75,and 1.0 mg/L) revealed the primary-secondary order of effects as IAA > 6-BA > 2,4-D. The optimal induction medium was MS + 30 g/L sucrose + 7.0 g/L agar + 700 mg/L casein hydrolysate + 2 mg/L 6-BA + 0.6 mg/L 2,4-D + 0.5 mg/L IAA,achieving a maximum somatic embryogenesis rate of 23.3%.For secondary embryo proliferation(cultured at 24±2 ℃ in darkness for 30 days),6-BA(P<0.01) and NAA(P<0.05) were identified as key factors.The best proliferation medium was MS + 30 g/L sucrose + 7.0 g/L agar + 700 mg/L casein hydrolysate + 0.1 mg/L 6-BA + 0.5 mg/L NAA + 600 mg/L inositol + 200 mg/L cyclodextrin,yielding a maximum proliferation rate of 20.17-fold.[Conclusion]This study significantly improves the efficiency of somatic embryogenesis and secondary embryo proliferation in L. cubeba,providing a technical foundation for its large-scale propagation.更多还原