甘露醇、蔗糖和低温预处理对花楸体细胞胚诱导的影响

Effects of Mannitol,Sucrose and Cold Pretreatment on Somatic Embryogenesis of Sorbus pohuashanensis (Hance) Hedl.

用渗透剂甘露醇和蔗糖以及2～5℃低温分别预处理未成熟合子胚外植体,研究其对花楸体胚诱导率影响的结果表明,未成熟的合子胚经1.0mol·L-1甘露醇预处理24h后,接种在添加0.5mg·L-16-BA、0.2mg·L-12,4-D和4%蔗糖的MS培养基上培养可产生大量体胚,体胚诱导率可达84%,显著高于未经甘露醇预处理的(诱导率为38%),每个外植体产生的体胚数可达12.9个。体胚经成熟和萌发培养后形成再生植株。扫描电镜观察表明,甘露醇预处理可改变外植体表面细胞的有序排列,改善体胚发生状况,因而体胚诱导率增加。

Effects of pretreatments with osmotica, mannitol and sucrose, and 2-5 ℃ cold storage on immature zygotic embryo explants of Sorbus pohuashanensis were conducted. The results showed that abundant somatic embryos formed and the their regeneration rate reached 84% on MS medium supplemented with 0.5 mg·L^-1 6-BA, 0.2 mg·L^-1 2,4-D and 4% sucrose after pretreatment with 1.0 mol·L^-1 mannitol for 24 h, average 12.9 somatic embryos per explant were induced, the regeneration rate was much higher than that of untreated explants （control, 38%）. The somatic embryos converted into plantlets successfully after maturation and germination culture. Scanning electron micrographs （SEM） revealed that pretreatment with 1.0 mol·L^-1 mannitol for 24 h disturbed the distribution pattern of the explant epidermal cells and the somatic embryogenesis was enhanced.