Study on rooting characteristics and occurrence model of adventitious roots in cuttage of Aronia melanocarpa

Abstract

Abstract [Objective] The aim of the study is to investigate the origin and development of the adventitious roots in cuttage of Aronia melanocarpa as well as to understand its mechanism. [Methods] Taking the semi-lignified cuttings of ‘Fukangyuan No.1’ as materials, the changes in internal structure and external morphology of the cuttings during the formation of adventitious roots were observed by hydroponic cutting technology and paraffin section method. [Results] The results showed that the rooting period of IBAtreated cuttings was 30-40 d under hydroponic conditions. During the cutting process, the adventitious roots were appeared at the lenticel at 10-15 d and at at the cutting incision 15-20 d, and the rooting speed, number, and root length were better than the control. The number of adventitious roots in the cuttings was the largest and the rooting was fast. Exogenous induction significantly improved rooting rate and quality. There was no latent root primordium in the cuttings before cutting, which was formed after cutting. The adventitious roots were formed into callus rooting type and internal meristem rooting type. The adventitious roots produced in the bark were originated from vascular cambium, phloem parenchyma cells, or cortex, while the adventitious roots produced by the callus were specialized by the parenchymal cells. Leaf gaps or branch gaps were the main areas for the formation of adventitious root primordia and the formation of callus. [Conclusion] The rooting of cuttings belongs to the multi-site mode and the induced rooting type.

Keywords

• aronia melanocarpa
• cutting
• adventitious root formation
• leaf gap
• branch gap