关键词: 兜兰, 兜兰, 层次分析法, 综合评价

Abstract: To understand the root characteristics of Gentiana scabra, we studied the developmental process and the anatomical structure of 1-4 year-old roots of G. scabra by using the routine observation and the paraffin methods. The results showed that: 1-year seedlings mostly belonged to tap root system, and more than 2-year plants developed into fibrous root system, the whole root system grew vertically downward or inclined to one side with the increase of root age; the structure of adventitious roots at different root ages was similar, consisting of epidermis, cortex and secondary vascular tissue from the outer to the inner; with the increase of root age, epidermis gradually shed completely, and the protective effect of the epidermis was replaced by its inner adjacent cortex and the mother cells of the outer cortex, its endodermis persisted, and no obvious periderm was seen at 4-year-old root; the vascular cambium composed of 2-5 layers of flat cells; the area of secondary phloem and secondary xylem increased step by step with the increase of root age, but the phloem parenchyma cells still accounted for the main part, secondary xylem was underdeveloped; a new structure appeared in the medullary center of some 4-year-old roots which was the pith endodermis. Therefore, the development and anatomical structure characteristics of roots of G. scabra are suitable for its growth environment, moreover, the development processes and functions of new structure which is the pith endodermis need to be further studied.