The Application of Tissue Clearing Technology in Experimental Course of Plant Anatomy and Plant Developmental Biology

Whole-mount tissue clearing and tissue section are useful techniques in plant anatomical and developmental researches. This paper designed an experimental course for undergraduate students to understand the developmental processes of plant lateral root, ovule (especially the embryo sac) and embryo. In this experiment, Arabidopsis seedlings, flower buds and seeds at different developmental stages were fixed, depigmented, and cleared. Then the cleared samples were observed under a microscope to identify lateral root, ovule and embryo at different developmental stages. After the root was cleared, eight developmental stages of the lateral root primordium from the formation of short initial cells to the emergence of the lateral root could be clearly observed under the microscope. After the ovules at sequential developmental stages were cleared, the megaspore mother cell, functional megaspore (FG1 stage) and embryo sacs at FG2 to FG7 stages could be clearly observed under the microscope. After the seeds at sequential developmental stages were cleared, embryos at the 1-cell stage, 8-cell stage, globular stage, heart stage, torpedo stage, bent stage and mature stage could be clearly observed under the microscope. This course will enable students to have a more systematic understanding of the lateral root, ovule and embryonic developmental processes of Arabidopsis and other dicotyledonous plants. This experiment is also suitable for other small-sized dicotyledonous plants.