[Phenotypic Trait Variation, Correlation and Path Analysis of Clerodendranthus spicatus]

To investigate the phenotypic trait variation range of Clerodendranthus spicatus, and to look for phenotypic traits closely related with its yield and quality, in order to provide reference for its breeding.

Randomly labelled plants of Clerodendranthus spicatus, observed its phenotypic traits and analyzed by variation, principal component, correlation and path analysis.

13 phenotypic traits in the 15 germplasms of Clerodendranthus spicatus had great variations, the variations mainly distributed in yield, growth and genetic characteristics. Correlation and path analysis showed that, the plant dry weight had an extremely significantly positive correlation with fresh weight, and a positive correlation with stem height, stem diameter and root diameter. Plant fresh weight had a majorly direct contribution to the plant dry weight, stem height, stem diameter and root diameter also had a direct contribution to the plant dry weight. The other characters, including root length, branches, the number of leaf nodes, leaf number, leaf length, leaf width, fresh weight/dry weight ratio, rosmarinic acid content and ursolic acid content all had a negatively direct contribution to the plant dry weight. Rosmarinic acid content had a positive correlation with fresh weight, and a significantly positive correlation with fresh weight/dry weight ratio. Fresh weight had a majorly direct contribution to the rosmarinic acid content, stem height and stem diameter also had a direct contribution to the plant rosmarinic acid content. The other characters, including root length, root diameter, branches, the number of leaf nodes, leaf length, leaf width, dry weight, fresh weight/dry weight ratio, and ursolic acid content all had a negatively direct contribution to the rosmarinic acid content.

The phenotypic traits of Clerodendranthus spicatus had rich variations on yield, growth and genetic characteristics. When choosing good germplasm, plant fresh weight, stem height, stem diameter and plant fresh weight/dry weight ratio having promoting effects on the plant dry weight and rosmarinic acid content should be considered comprehensively, and plant with vigorous growth, tall stem and more leaves can be choosed firstly.