菠萝蜜叶绿素缺失突变体幼苗维管组织结构分析

Vascular Tissue Structure Analysis of Chlorophyll Deficient Mutant Seedlings from Artocarpus heterophyllus

木本植物维管组织发育对木材形成意义重大。本研究利用石蜡切片法和光学显微技术,研究菠萝蜜(Artocarpus heterophyllus)叶绿素缺失突变体(chlorophyll deficient mutant,CDM)幼苗不同部位的维管组织结构,观察及测量导管分子、筛管分子的孔径和密度等,分析了维管组织和形成层的特点。结果表明,CDM幼苗的根、茎、叶柄和叶主脉维管组织中的木质部和韧皮部的结构均发生改变。与正常苗相比,CDM幼苗中次生木质部导管分子和韧皮部筛管分子的孔径和面积减小,密度增大;根和茎维管组织中形成层厚度减小,层数减少;CDM茎中的维管组织相比于根显示出更强的抑制作用。本研究为进一步探索木本植物维管组织发育提供了新材料。

The development of the vascular tissue in woody plants is of great significance to wood formation.In this paper,the method of paraffin section and optical microscopy were used to study the vascular tissue structure of different parts of chlorophyll deficient mutant(CDM)from Artocarpus heterophyllus.The pore size and density of vessel ele-ments and sieve tube elements were observed and measured,and the characteristics of vascular tissue and cambium were analyzed.The result showed that the structure of the xylem and phloem in the vascular tissue of CDM seedlings’roots,stems,petioles and leaf main vein were changed.Compared with the normal seedlings,the pore size and area of the secondary xylem vessel elements and phloem sieve vessel elements decreased and the density of those increased in CDM seedlings.The thickness of cambium decreased and the number of layers decreased in the vascular tissue of root and stem in CDM.The vascular tissue in the stems of CDM showed stronger inhibition compared with that in the roots.This study would provide new materials for further exploring vascular tissue development of woody plants.