掌叶半夏悬浮培养下的体细胞胚胎发生的研究

Studies on Somatic Embryogenesis of Pinellia pedatisecta Schott

掌叶半夏(Pinellia pedatisecta Schott)种子在附加2,4-D2.0,BA0.5mg/L的MS培养基上形成浅黄色或白色颗粒状胚性愈伤组织。胚性愈伤组织在附加2,4-D1.0,BA0.5,CH300mg/L的MS液体培养基中振荡培养,可产生大量的体细胞胚。2,4-D对体胚诱导效果显著并促进其早期发育,但抑制其进一步发育成熟。NAA对体胚诱导效果不如2,4-D,但可使体胚正常发育。水解酪蛋白明显提高体胚诱导频率。显微观察表明:体胚起源于单个胚性细胞,胚性单细胞经极性分裂形成二细胞、三细胞、多细胞原胚,再经球形胚、梨形胚、子叶分化期胚到成熟胚;同时,还观察到类似双子叶植物合子胚发育过程中的心形胚和鱼雷胚。另外,还观察到连体胚、次生胚等畸形胚。成熟体胚转移到分化培养基上,可发育为正常小植株。

Seeds of Pinellia pedatisecta Schott were cultured on MS medium containing 2. 4-D 2. 0, BA0. 5 mg/L and embryogenic callus was induced. After the embryogenic callus was suspended in the liquid medium MS containing 2, 4-D 1. 0, BA0. 5, CH300 mg/L, a lot of somatic embryos emerged. 2, 4-D was suitable for induction of embryos but inhibitted their further development . Induction effect on embryogenesis of NAA was inferior to that of 2, 4-D, but facilitate further development and growth of embryos. Casein hydrolysate (CH) improved the rate of embryogenesis. Somatic embryos of pinellia pedatisecta schott originated from single embryogenic cells, viaglobular and pear-shaped, or globular, heart-shaped and torpedo-shaped embryos, to mature embryos. When the somatic embryos were transferred to differentiated medium, most of them germinated and grew as normal plantlets.