野生早樱试管苗不定根发生的解剖学研究

Anatomical Study on Adventitious Root Formation of Cerasus subhirtella var.ascendens in Vitro

采用石蜡切片法对野生早樱(Cerasus subhirtella var.ascendens)试管苗生根过程进行解剖学研究,结果表明,野生早樱试管苗的幼茎从外至内由表皮、皮层、中柱三部分组成;茎内无潜伏根原基,不定根为诱生根原基发育形成,由髓射线与形成层交叉处的薄壁细胞分裂、分化形成;髓射线、韧皮薄壁细胞及皮层薄壁细胞均能分裂形成愈伤组织,愈伤组织内分化出厚壁组织,在部分愈伤组织可内分化出不定根原基,不定根的维管束未能与茎的维管束相连,这是造成试管苗移栽成活率较低的原因之一。

By means of paraffine section and microscopic study on root of test-tube seedling in Cerasus subhirtella var.ascendens, the results showed as follows：The stems of plantlets were composed of three parts from periphery to center, e.g.epidermis,cortex,and vascular cylinder.The induced root primordium developed into the adventitious root, and it orginated from the division and differentiation of the vascular cambium cell touching with the pith ray.Callus tissue formed pith ray and parenchyma in cortex and phloem, could form adventitious root primordium and much sclerenchyma.The vascular tissue of the root and the stem did not joined, which was one of the reasons made low suvival rate of transplants.