建立甜高粱(Sorghum bicolor)高频、高效再生体系的研究

Research on Establishment of a Highly Frequent and Efficient Regeneration System of Sorghum bicolor

【目的】建立能源植物甜高粱(Sorghum bicolor L.Moench)的高频、高效离体培养再生体系,为遗传转化奠定基础。【方法】以甜高粱品种凯勒的芽顶端分生组织为外植体,探讨在甜高粱直接诱导丛生芽的培养过程中,无菌实生苗的适合苗龄,适宜的激素组合与比例;并将获得的最佳培养方法应用于其它两个甜高粱品种:M-81E和意达利,以研究此途径的基因型依赖性。【结果】利用3d苗龄的芽顶端分生组织作为外植体容易获得较高的分生组织膨大率。甜高粱丛生芽诱导的适宜激素组合为4.0mg·L-16-苄基腺嘌呤+0.5mg·L-12,4-二氯苯氧乙酸+0.5mg·L-1噻重氮苯基脲,可获得91%的丛生芽诱导频率。适合甜高粱快速生根的激素配方为0.5mg·L-1萘乙酸。通过芽顶端分生组织直接诱导丛生芽途径,每个外植体可诱导出上百个芽,最终产生30—40株再生苗。M-81E和意达利具有与凯勒相似的丛生芽诱导频率及效率。【结论】本研究成功地建立了甜高粱的高频、高效离体培养再生体系,且具有外植体来源不受限制,基因型依赖性弱,遗传稳定性好的优点。

【Objective】 The objective of this research was to establish a highly frequent and efficient regeneration system of sweet sorghum（Sorghum bicolor L.Moench）,a kind of energy plants,so as to make preparation for genetic transformation.【Method】 The shoot apical meristems of sweet sorghum Keller were used as explants to investigate the effect of seedling age,phytohormone combinations and their ratios on the direct induction process of multiple shoots.Whether this regeneration pathway is less genotype-dependent in sweet sorghum,and whether the optimal culture method obtained above could be extended to other two genotypes,M-81E and Italian,were studied.【Result】 It was easier to obtain a high meristem enlargement percentage using the shoot apical meristem from 3-day-old sterile seedlings as the explants.The optimal phytohormone combinations for multiple shoot induction of sweet sorghum were 4.0 mg·L-1 6-benzylaminopurine ＋ 0.5 mg·L-1 2,4-dichlorophenoxyacetic acid ＋ 0.5 mg·L-1 thidiazuron,in which 91% of multiple shoot induction could be achieved.Naphthaleneacetic acid at 0.5 mg·L-1 markedly increased rooting rate of multiple shoots.One explant with shoot meristem could be induced to produce above 100 multiple shoots,and finally 30-40 regenerated plants were produced through a directly-induced multiple shoot pathway.M-81E and Italian had a similar induction percentage and efficiency of multiple shoots as Keller.【Conclusion】 A highly frequent and efficient regeneration system of sweet sorghum was successfully established,which has a sustainable explant supply,less genotype-dependence and good genetic stability.