TY - JOUR

T1 - Laser wounding pattern in relation to vascular tissue development for the stimulation of adventitious root formation in rose cuttings

AU - Morales Orellana, Raul Javier

AU - Winkelmann, Traud

AU - Rath, Thomas

N1 - Publisher Copyright: © 2024

PY - 2024/12/1

Y1 - 2024/12/1

N2 - The stimulation of adventitious root formation from laser-wounded rose cuttings in our previous study suggests that exposing the phloem proximities is one of the most relevant aspects for a positive effect on rooting response. But, the specific dimensions that wound patterns must fulfill to optimize rooting promotion remain unknown. This study analyzed the effect of wounded area and wound perimeter of laser marking patterns on the development of phloem, xylem, and callus using cross sections of single-leaf cuttings of Rosa canina 'Pfänder'. Four distinct laser patterns were designed and marked along the cutting base. Among these, three patterns were based on longitudinal strips, while one pattern was characterized by small squares, resulting in two distinct wound area levels and four wound perimeter levels. Periodic evaluations of stem sections showed that the development of phloem and xylem was significantly influenced by the pattern's geometry. Larger dimensions of xylem were associated with patterns of greater area and a smaller perimeter, while an increase in phloem was related to patterns of longer perimeter distributed in smaller areas. The maximum rooting success in wounded cuttings reached 44% in contrast to 9% observed in the control group in the absence of additional wounds. The development of vascular tissue was significantly correlated with adventitious rooting, with phloem being more closely linked with a Pearson coefficient of 0.92 compared to 0.30 for xylem. Additionally, a negative Pearson coefficient of −0.92 between the ratio area: perimeter and adventitious root formation showed that laser patterns with large wounded area with less borders led to a reduced rooting response. The results provide evidence of how wounded tissue contributes to the intrinsic development of adventitious roots and reveal the importance of proper wound dimensions.

AB - The stimulation of adventitious root formation from laser-wounded rose cuttings in our previous study suggests that exposing the phloem proximities is one of the most relevant aspects for a positive effect on rooting response. But, the specific dimensions that wound patterns must fulfill to optimize rooting promotion remain unknown. This study analyzed the effect of wounded area and wound perimeter of laser marking patterns on the development of phloem, xylem, and callus using cross sections of single-leaf cuttings of Rosa canina 'Pfänder'. Four distinct laser patterns were designed and marked along the cutting base. Among these, three patterns were based on longitudinal strips, while one pattern was characterized by small squares, resulting in two distinct wound area levels and four wound perimeter levels. Periodic evaluations of stem sections showed that the development of phloem and xylem was significantly influenced by the pattern's geometry. Larger dimensions of xylem were associated with patterns of greater area and a smaller perimeter, while an increase in phloem was related to patterns of longer perimeter distributed in smaller areas. The maximum rooting success in wounded cuttings reached 44% in contrast to 9% observed in the control group in the absence of additional wounds. The development of vascular tissue was significantly correlated with adventitious rooting, with phloem being more closely linked with a Pearson coefficient of 0.92 compared to 0.30 for xylem. Additionally, a negative Pearson coefficient of −0.92 between the ratio area: perimeter and adventitious root formation showed that laser patterns with large wounded area with less borders led to a reduced rooting response. The results provide evidence of how wounded tissue contributes to the intrinsic development of adventitious roots and reveal the importance of proper wound dimensions.

KW - Adventitious root formation

KW - Histology

KW - Laser wounding

KW - Rosa canina 'Pfänder'

KW - Stem cutting

KW - Vascular tissue

UR - http://www.scopus.com/inward/record.url?scp=85204128758&partnerID=8YFLogxK

U2 - 10.1016/j.scienta.2024.113647

DO - 10.1016/j.scienta.2024.113647

M3 - Article

AN - SCOPUS:85204128758

VL - 338

JO - Scientia horticulturae

JF - Scientia horticulturae

SN - 0304-4238

M1 - 113647

ER -