Osha (Ligusticum porteri) is a Rocky Mountain native used as a medicinal herb. Studies are underway to commercially propagate and produce the plant. In an attempt to increase rooting success of crown cuttings taken from osha, five different media were used in conjunction with three commercial mycorrhizal inoculants and a control. Field soil and a pre-mixed commercial product were tested in combinations of 100/0, 75/25, 50/50, 25/75, and 0/100 percent by volume. Each of three commercially-available mycorrhyzal inoculants were tested with each media. Crown cuttings of osha were taken and stuck on 29 Aug. 2003 and were placed on a greenhouse mist bench. Data were taken on days to rooting. Results showed no differences among the media or the inoculants and no interactions were present. There was no benefit in decreased days to rooting with additions of mycorrhizae. There were no responses to different media.
Bennett J. Sondeno and Karen L. Panter*
Bennett J. Sondeno and Karen L. Panter
Osha (Ligusticum porteri) is a Rocky Mountain native frequently used as a medicinal herb. It is currently harvested largely from the wild. Studies have been under way since 2001 to find ways to propagate and produce the plant. To potentially increase rooting success of crown cuttings of osha, two different rooting hormones were used, each at two concentrations. Treatments were controls, 2500 ppm, and 5000 ppm solutions each of indole-3-butyric acid (IBA) and α-naphthalene acetic acid (NAA). Cuttings were soaked in deionized water or treatment solutions for 2 min. After soaking cuttings were stuck in sterilized sand in 725-mL2 containers, one cutting per container. Containers were placed on a mist propagation bench at 21 °C in a completely randomized design under natural light and day lengths. Data taken were days to visible root and shoot, and presence or absence of root formation after 50 days. Results indicated only one of 70 cuttings (<1%) produced a shoot. Roots formed on 14% of control cuttings, 64% in 2500 ppm IBA, 86% in 5000 ppm IBA, 36% in 2500 ppm NAA, and 14% in 5000 ppm NAA. Days to rooting ranged from 14.9 (2500 ppm IBA) to 29.0 (5000 ppm NAA). Due to considerable variation in days to rooting, and the number of cuttings that did not root, analysis of variance showed no differences among treatments. Frequency analysis indicated differences among treatments in root presence or absence. The 2500 and 5000 ppm IBA treatments showed more root formation than the controls or either NAA treatment. This indicates IBA may enhance rooting of osha crown cuttings.