Study On The Shoot Cutting Propagation Technology And Rooting Mechanism Of Viburnum Trilobum

Viburnum trilobum is a deciduous shrub of the genus Viburnum in Adoxaceae.It has lush branches and leaves,bright red fruits,and a long winter survival period.It is a precious seasonal ornamental plant in urban landscaping.This tree species has high resistance,strong adaptability,high economic value,and broad application prospects.In order to broaden the propagation mode of V.trilobum and better promote its garden application and development,this paper conducted a systematic study on the softwood cutting technology of V.trilobum from four aspects:cutting substrate,cutting location,hormone concentration,and hormone treatment time.The dynamic changes in nutrients,oxidase activity,and endogenous hormones during the rooting process were analyzed to explore its rooting mechanism.The specific research results are as follows:（1）The best combination for the rooting effect of V.trilobum twig cutting is A4B4C1D1,which is soaked in an IBA rooting solution with a concentration of 100mg/L for 5minutes before cutting in a sandy soil:vermiculite（1:1）matrix.Cutting media significantly affected the rooting characteristics of V.trilobum（P<0.01）,with V.trilobum having the highest rooting characteristics in sandy soil:vermiculite（1:1）,reaching 93.78%,followed by sandy soil:vermiculite（2:1）,with a survival rate of 93%;In the experiment of different branch positions,the survival rate of V.trilobum using the upper part of the branch was the best,reaching 91.14%.The rooting characteristics such as root number,root length,and root diameter were higher than those of other treatments;Based on the rooting indicators such as survival rate,root length,root diameter,and root number of cuttings,V.trilobum should be soaked in IBA rooting solution with a concentration of 100 mg/L for 5 minutes for the best rooting effect in terms of hormone concentration and hormone treatment time.Plant growth regulator IBA can improve the metabolism of nutrients and accelerate the rooting process of cuttings;The content of soluble protein is lower than that of soluble sugar and starch,and the dynamic range of change is relatively small,indicating that soluble sugar and starch are the main influencing factors during the rooting process of V.trilobum tender branch cutting.（2）Plant growth regulator IBA can improve the metabolism of nutrients in cuttings and accelerate the rooting process;The content of soluble sugar and starch is higher than that of soluble protein,and the dynamic range of changes is also large.During the tender branch cutting process of V.trilobum,soluble sugar and starch are the main factors affecting rooting.（3）The changes of oxidase activity in V.trilobum cuttings are closely related to cuttings rooting.Low activity POD promotes adventitious root induction,while high activity POD promotes adventitious root elongation;High activity PPO promotes adventitious root induction;There is a fluctuating relationship between IAAO activity and IAA content;Plant growth regulator IBA can enhance the activities of POD and PPO,reduce the activity of IAAO,and is conducive to cuttings rooting.（4）During the rooting process of V.trilobum,high content of IAA promotes the induction of adventitious roots in cuttings;Low content of ABA promoted the elongation of adventitious roots in cuttings;Low content of ZR can promote adventitious root induction in cuttings,while high content of ZR can promote cell division and growth in cuttings;Low content of GA₃promoted the elongation of adventitious roots in cuttings;The ratio of IAA/ABA and IAA/ZR of cuttings treated with IBA can accelerate the rooting process and facilitate the rooting of cuttings.