Abstract:

This study aims to investigate the early performance characteristics of asexual lines derived from tissue culture, preliminarily establish the uniformity of these lines, and explore early evaluation methods for the selection of superior Idesia polycarpa varieties. Two-year-old I. polycarpa ‘Exuan 1’ tissue culture asexual saplings were selected as the research subjects. The study involved an analysis of various parameters, including sapling height, ground diameter, number of branches, height under the branch, crown width, branch length and angle, and the angle between branches. A phenotypic evaluation of the above-ground vegetative organs was conducted. The results showed that the average ground diameter of the two-year-old I. polycarpa ‘Exuan 1’ tissue culture asexual saplings was 18.40 cm, with an average height of 128.5 cm, and an average height under the branch of 71.67 cm. The number of branches was consistently five, and as the position of the branches rose, the average length of the branches tended to decrease, following a Logistic model. The branching angles were relatively consistent, averaging 52.83°. The angle between vertically adjacent branches remained relatively stable, averaging 142.19°, and the angle between horizontally adjacent branches was also consistent, averaging 72°. These findings indicate that the I. polycarpa ‘Exuan 1’ tissue culture asexual saplings demonstrate good uniformity.

Key words: Idesia polycarpa, tissue culture, clone, phenotype, seedling stage