黑麦草高效丛生芽的发生及离体开花的初步研究

High efficiency production of multiple shoots and inflorescences induction from the shoot of Lolium multiflorum and L.perenne

以一年生和多年生黑麦草优良品种为材料,取无菌种子苗的茎尖生长点部分在加有不同浓度的2,4-D和6-BA的MS诱导培养基上诱导丛生芽发生,然后在加有不同浓度6-BA的增殖培养基上产生大量丛生芽,并长期继代培养。从丛生芽块上剥取单芽转移到生根培养基上诱导根的发生,生根植株移栽成活率达100%。本试验建立了一种诱导频率高、增殖速度快、试验周期短的黑麦草丛生芽离体培养体系。在附加适宜浓度6-BA和ABA的培养基上丛生芽可直接分化出大量花序,40 d后产生花序的芽块频率最高为81%。进而研究了光照、激素和继代培养时间等因素对黑麦草离体开花的影响。

The report presented here details a procedure for Lolium multiflorum and L. perenne in vitro propa gation using cultured shoot apical meristems at a high frequency. Shoot apices from 1-week-old aseptically germinated seedlings were cultured on MS medium containing suitable concentrations of 2,4-D and 6-BA, multiple sboot clumps were induced at a high frequency. Following this the cultures were sub-cultured on shoot proliferation medium supplemented with different concentrations of 6-BA, with the most efficient proliferation medium found 1o be MS ＋ 2.0 mg/L 6-BA. When the shoot clumps developed into a sufficiently larger size, shoots were cut oul and transferred to a root inducing medium （1/2 MS＋1.0 mg/L NAA） with white roots generally developed after 9 d of cuhure. One month later vigorous plantlets were transplanted to pots and the survival rate of the plantlets was shown to be up to 100%. The study reported here has established a system of in vitro multiple shoot clumps culture for ryegrass, which features efficient induction, rapid proliferation and only requires a short period, which in all is suilable for cellular engineering and genetic manipulation of ryegrass, lnflorescences were induced from multiple shoot clumps on suitable flower-inducing media. On the most suitable medium, the highesl frequency of flowered shoot clumps was 81 % after 40 days culture. Further the effect of light, hormone, and culture duration on in vitro flowering was investigated.