Abstract: In order to establish a highly efficient regeneration system of multiple shoots in perennial Ryegrass,shoot apices of sterile seedlings were used as explants.The induction and proliferation of multiple shoots from three cultivars(Regal,Belle and Marathon) of perennial ryegrass were studied to understand essential requirements of establishing a transformation receptor system.Results showed that: 0.5 mg·L^-1 2,4-D and 2.0 mg·L^-1 6-BA were suitable hormone combinations to induce multiple shoots from shoot apices.The best hormone for propagating multiple shoots was 2.0 mg·L^-1 6-BA.However,growth of multiple shoots was inhibited by increasing subculture times.Genotypes also have impact on the induction and proliferation of shoot clumps.The best rooting medium is 1/2MS+NAA 0.1 mg·L^-1.Both G418(15 mg·L^-1) and Hyg(75 mg·L^-1) were demonstrated as selection agents for transformation system in Ryegrass.Data provide general guidelines for the development of a transformation receptor system in ryegrass with high frequency induction and a rapid,short proliferation period.

Key words: Lolium Perenne L., Shoot apices, Multiple Shoots, Propagation, Screening agent, Subculture

摘要： 选取多年生黑麦草(Lolium Perenne L.)的3个优良品种:里加(Regal)、贝尔勒(Belle)、马拉松(Marathon)作为植物材料,以无菌苗的茎尖为外植体,对多年生黑麦草丛生芽的诱导、增殖进行研究,以其建立多年生黑麦草丛生芽高频增殖体系,并在此基础上确定丛生芽离体培养的最适筛选剂及其浓度。结果表明:当2,4-D和6-BA浓度分别为0.5 mg·L^-1和2.0 mg·L^-1时有利于茎尖诱导产生丛生芽;丛生芽增殖的最适6-BA浓度为2.0 mg·L^-1;继代培养时间过长对丛生芽块的生长不利;基因型对丛生芽的诱导和增殖有很大影响;适宜的生根培养基为1/2 MS+NAA 0.1 mg·L^-1。此外,还确定了丛生芽的最适筛选剂为G418和Hyg,其浓度分别为150 mg·L^-1和75 mg·L^-1。从而,建立了一种诱导率和增殖率较高并且实验周期短的丛生芽高频增殖培养体系,并进一步探讨了建立多年生黑麦草遗传转化受体系统的必要条件。

关键词: 多年生黑麦草, 茎尖, 丛生芽, 增殖, 筛选剂, 继代培养