Author
Scagel, Carolyn | |
REDDY, K - MEADOW LAKE NURSERY | |
ARMSTRONG, J. - MEADOW LAKE NURSERY |
Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/1/2002 Publication Date: 1/1/2003 Citation: Scagel, C.F., Reddy, K., Armstrong, J.M. 2003. Mycorrhizal fungi in rooting substrate influences the quantity and quality of roots on stem cuttings of Hick's yew. HortTechnology. 13(1):62-66. Interpretive Summary: The benefits from root colonization by mycorrhizal fungi are thought to be highest when colonization occurs as early as possible during plant growth. In a commercial nursery we assessed whether (1) addition of VA mycorrhizal fungi (VAMF) inoculum into rooting medium during cutting propagation would increase rooting and (2) the quantity of inoculum influenced rooting of Taxus x media 'Hicksii'. Although the degree of response of Taxus cuttings to VAMF inoculum varied with the level of inoculum, our results indicate that adding VAMF inoculum into the rooting medium is equal to or better than the rooting response obtained by using rooting hormone under the nursery production conditions. When determining what inoculum levels to use during cutting propagation, growers should run trials at different levels since our results indicate that increasing the quantity of VAMF inoculum in the rooting medium can increase root growth, however there may be certain levels of VAMF inoculum which increase root initiation without increased root growth. In our experiment, although VAMF inoculum did not increase root growth at some of the inoculum levels tested, inoculation could result in a higher quality cutting that is better able to withstand the stress of transplanting and grow during later stages of plant development. Technical Abstract: The benefits from root colonization by mycorrhizal fungi are thought to be highest when colonization occurs as early as possible during plant growth. In a commercial nursery we assessed whether (1) addition of VA mycorrhizal fungi (VAMF) inoculum into rooting medium during cutting propagation would increase rooting and (2) the quantity of inoculum influenced rooting of Taxus x media 'Hicksii'. Fifteen weeks after cuttings were stuck, root initiation was higher when cuttings were stuck in rooting media containing VAMF inoculum. Increasing the quantity of VAMF inoculum in the rooting medium increased root growth during the early stages of rooting, however there were certain levels of VAMF inoculum that increased adventitious root initiation without increased root growth. Increases in root initiation and growth in response to adding VAMF inoculum into the rooting medium can decrease the amount of time for cuttings to attain an adequate amount of roots for transplanting and increase the quality of rooted cutting obtained. Our results indicate that if inoculum from mycorrhizal fungi is used during propagation from cuttings, there may be optimal levels of VAMF inoculum required to alter the initiation and growth of roots. |