Cu、Zn制剂对紫花风铃木苗期生长和根系形态的影响OA

[Objective]To investigate the root-controlling effects of different chemical agents,and provide theoretical references for Handroanthus impetiginosus container seedlings cultivation.[Method]A controlled-root experiment was conducted on H.impetiginosus container seedlings under a two-factor randomized block design.Treatments with different concentrations of cupreous and zincous preparations were applied to evaluate their effects on seedling growth characteristics and root morphology during the early growth stage.[Result]Cu and Zn agents had limited influence on seedling height and ground diameter,but significantly improved the quality index of seedlings of H.impetiginosus.Cu agents and high concentration Zn agents significantly increased the aboveground biomass,belowground biomass,and total biomass.Cu agents significantly enhanced both coarse and fine root biomass,whereas Zn agents exhibited promotive effect exclusively on fine root biomass.Cu agents and Zn agents had significantly promotion effects on root morphological parameters,including total root length,root surface area,root volume,and root tip number.Additionally,Cu and Zn agents significantly altered root structure by reducing the root average diameter and markedly enhancing the growth and proportion of fine roots,particularly extremely fine roots(0-0.5 mm).These changes promoted the development of the root system toward a"fine-root-dominated"structural pattern.The root-control effects of Cu agents was slightly higher than that of Zn agents,and the promotion effects of Cu agents on extremely fine roots(0-0.5 mm)was significantly better than that of Zn agents,while there was little difference between the root-control effects of the two chemical agents in other aspects.[Conclusion]H.impetiginosus demonstrates pronounced tolerance to copper(Cu)and zinc(Zn),supporting the implementation of chemical root control techniques for container seedling cultivation.Based on comprehensive analysis of the growth and root morphology,120 g/L Cu agent is recommended as the optimal chemical root control reagent for the seedling cultivation of H.impetiginosus.