Evaluation of substrate composition and exogenous hormone application on vegetative propagule rooting success of essential oil hemp (Cannabis sativa L.)

PLoS One. 2021 Jul 29;16(7):e0249160. doi: 10.1371/journal.pone.0249160. eCollection 2021.

Abstract

To support the rapidly expanding industrial hemp industry, a commercial supply of high-quality starter plants with low genetic variability from nurseries will be key to consistent and efficient cultivation efforts. Rooting success was evaluated across four propagation medias, five rooting hormones, and eight commercially available high-cannabidiol (CBD) essential oil hemp cultivars. Cuttings were placed in a climate-controlled room and assessed for rooting success 12 days after cloning. Rooting success was determined by quantifying total root number, cumulative total root length, and total root mass. Propagation media had the greatest effect on rooting success (13-80%). Rockwool had the highest rooting success resulting in 10-fold increases in rooting traits over the next highest scoring medium (Berger BM6). Hormone applications significantly improved (15- to 18-fold) rooting success compared to no hormone application, while non-statistical differences were observed across auxin hormone concentrations and application methods. Genetic variation in rooting response was observed between cultivars with 'Cherry Wine' outperforming all other cultivars with an approximate 20% increase in rooting success over the next highest rooting cultivar, 'Wife'. Although the ideal combination was not specifically identified in this study, findings provide insight into how rooting hormone application and medium selection impact vegetative propagule rooting success of essential oil hemp.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cannabis / chemistry*
  • Cannabis / drug effects*
  • Indoleacetic Acids / pharmacology
  • Oils, Volatile / analysis*
  • Plant Growth Regulators / pharmacology*

Substances

  • Indoleacetic Acids
  • Oils, Volatile
  • Plant Growth Regulators

Grants and funding

The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. This project was made possible by financial support from Green Roads, LLC and the UF/IFAS Office of the Dean and Research. Green Point Research, Green Roads LLC, and ANO Colorado LLC donated the cultivars used in this research. Steven Anderson was funded by Roseville Farm’s UF/IFAS Florida Industrial Hemp Endowment contribution.