PJB-2024-103
Comparative anatomical study on laticifers in six Apocynaceae species
Jianhua Zhang, Yue Liu, Taibo Xue, Chunli Hu and Meng Zhao
Abstract
This study examined six species from three subfamilies of Apocynaceae – Cynanchum thesiodes, Periploca sepium, Cynanchum chinense, Asclepias curassavica, Metaplexis japonica, and Catharanthus roseus to characterize the structure and distribution of laticifers, providing an anatomical basis for further research on laticifer biology and Apocynaceae taxonomy. Using comparative anatomical methods, we investigated the type, size, and distribution of laticifers in stems and leaves. In stems, all species possessed non-articulated, unbranched laticifers located in both the cortex and pith. In leaves, C. thesiodes, P. sepium, and C. chinense contained articulated, branched laticifers; A. curassavica and M. japonica had non-articulated, branched laticifers with Y-shaped branches; and C. roseus exhibited articulated, unbranched laticifers. Across all species, leaf laticifers were mainly distributed within the spongy mesophyll and outside the palisade cells, with occasional occurrence external to the phloem