壳寡糖对不结球白菜子叶离体培养再生体系的影响

Effects of Chitosan Oligosaccharide on Non-Heading Chinese Cabbage Cotyledon Regeneration

以不结球白菜(Brassica campestris L.ssp.chinensis Makino)子叶为外植体,考察壳寡糖对不结球白菜子叶离体培养再生体系的影响。在添加外源激素6-BA和NAA的条件下,比较了不同浓度(0.5、1.0、2.0和10.0 mg·L-1)壳寡糖对不结球白菜子叶形成愈伤组织、再生芽和再生不定根的影响。实验结果表明,低浓度的壳寡糖能促进子叶形成愈伤组织、再生芽。壳寡糖促进子叶形成愈伤组织和再生芽的最适浓度为0.5 mg·L-1,与其他浓度壳寡糖处理组相比,该浓度壳寡糖促进了子叶愈伤组织的形成,使出愈率达到92%。此外,该浓度壳寡糖能提高子叶的芽再生频率,使再生率达到80%,同时再生芽长度、叶绿素含量及外植体总鲜重达到最大,均显著高于对照组。然而,壳寡糖对再生芽生根有抑制作用,形成的不定根数目、平均根长和最长根长度均小于对照组。

The cotyledon of non-heading Chinese cabbage （Brassica campestris L. ssp. chinensis Makino） was used as explants to investigate the effects of chitosan oligosaccharide （COS） on regeneration system. Under the condition of adding 6-BA and NAA, the effects of four different concentrations （0.5, 1.0, 2.0, 10.0 mg L^-1） of COS on formation of callus, regenerated shoot and adventitious root were evaluated. The results showed that the formation of callus and regenerated shoot of Chinese cabbage cotyledon was significantly promoted by COS. The effective promotion concentration of COS on formation of callus and regeneration of shoot was 0.5 mg.L-1. Compared with the control, callus induction rate and shoot regeneration rate reached 92% and 80% at 0.5 mg-LJ COS. Length of regenerated shoot, contents of chlorophyll of shoot and fresh weight of explants were higher evidently than the control. Otherwise, the root formation of regenerated shoot was inhibited by COS, and the amounts of roots, length of root and length of longest root were lower than the control.