Response of Oaks and Elm to Soil Inoculations With Mycorrhizal Fungi and Rhizobacteria in a Nursery    (View PDF)

Balakrishna Rao, Donald H. Marx, and Brian Jeffers

Abstract: Live oak (Quercus virginiana), laurel oak (Q. laurifolia), and Drake elm (Ulmus parvifolia) seedlings were grown for 1 year in 4 L (1 gal) containers and then transplanted on 3 m (10 ft) centers at a nursery in Florida, U.S. Two years later, in April 2002, ten seedlings per tree species were treated by (1) soil injection with mycorrhizal fungi and rhizobacteria; (2) drenching with rhizobacteria and soil fungi applied monthly for 5 months; (3) a combination of (1) and (2); (4) drenching with SubdueŽ fungicide; or (5) nontreated controls. Root growth and mycorrhizal development were measured with root ingrowth cores. After 1 year (1 April, 2003), mycorrhizal development and root growth as well as stem calipers were greater in treatments containing the mycorrhizal fungi for all three species. The rhizobacteria treatment also increased root and stem growth on Drake elm. The fungicide, Subdue, did not significantly affect mycorrhizal development or root or stem growth. There were few naturally occurring mycorrhizae on roots of trees in this nursery.

Keywords: Ectomycorrhizae; vesicular-arbuscular mycorrhizae (VAM)

https://doi.org/10.48044/jauf.2006.008