提高菜心离体植株再生频率的研究

ENHANCEMENT OF PLANT REGENERATION RATE OF BRASSICA PARACHINENSIS CULTURED IN VITRO

ＡｇＮＯ３与ＡＢＡ 相配合，在离体培养条件下从３个菜心（Ｂｒａｓｓｉｃａ ｐａｒａｃｈｉｎｅｎｓｉｓＢａｉｌ．）品种（“４９－１９”、“６０Ｄ”和“７０Ｄ”）获得了高频率的植株再生。结果表明：在试验的３种外植体中，子叶－子叶柄再生能力最强。实生苗龄及接种方式影响植株再生频率。ＭＳ附加不同浓度的ＢＡＰ和ＮＡＡ，ＢＡＰ ２ ｍ ｇ／Ｌ与ＮＡＡ １ ｍ ｇ／Ｌ配合效果最好，植株再生频率可达２６．８％ 。培养基中单独添加ＡｇＮＯ３ 或ＡＢＡ 均能促进植株再生，且ＡｇＮＯ３ 作用优于ＡＢＡ。ＡｇＮＯ３（４ ｍ ｇ／Ｌ）和ＡＢＡ（０．５ ｍ ｇ／Ｌ）相配合获得了更高的植株再生频率：“４９－１９”达８９％ ，“６０Ｄ”达８４．３％ ，“７０Ｄ”达８６％ 。组织学研究表明，在本实验条件下菜心离体培养植株再生方式为外植体直接出芽。不定芽起源于子叶柄切口端维管组织的薄壁细胞；由此种细胞分裂形成分生细胞团，继而分化成芽。

Among the major factors affected plant regeneration in Brasica parachinensis,a combination of BAP (bacterial alhaline phosphatase) and NAA,at a concentration of 2 mg/L and 1 mg/L respectively, could raise 26.8% of the regeneration rate.It was also found that AgNO 3 or ABA when supplemented in the culture medium could increase the plant regeneration rate by 79.0% and 32.3% respectively,indicating that AgNO 3 was superior to ABA as a single factor.With a combination of AgNO 3 (4 mg/L) and ABA (0.5 mg/L) added to MS medium already supplemented with ABA 2.0 mg/L and NAA 1.0 mg/L the authors had achieved remarkable results in frequency increase of 89.0%,84.3% and 86.0% in three explant varieties of B.parachinensis,viz“49 19”,“60D” and “70D”,respectively.Among the three explants (cotyledon, hypocotyl and petiole with cotyledon), petiole with cotyledon possessed the highest capability for plant regeneration.In addition the age of seedlings and mode of inoculations also influenced the frequency of plant regeneration. Histological observation evidenced that the mode of plant regeneration in B. parachinensis was of organogenesis. Adventitions buds derived from the cells of vascular parenchyma at the cut surface of petioles. Mature plants were developed after the plantlets were transferred into the plot.