Native vs commercial mycorrhizal inoculum to promote the establishment of
Calochortus weedii var. intermedius

Lea Corkidi*1, Jeff Bohn1, John Ko2 and Margot Griswold3 .
1Tree of Life Nursery, 33201 Ortega Highway, San Juan Capistrano CA 92675. 2EDAW/AECOM. 240 East Mountain Ave., Fort Collins CO 80524. 3Earthworks Restoration, Inc. 2116 Arlington Ave., Los Angeles CA 90018

One of the soil components which may enhance the establishment of rare species as Calochortus weedii var. intermedius (intermediate mariposa lily), is the presence of arbuscular mycorrhizal (AM) fungi. The symbiotic association of plants with AM fungi improves their ability to cope with environmental stress by facilitating nutrient uptake; by increasing tolerance to drought, and resistance against soil pathogens; and by enhancing soil aggregation. However, since there are different levels of functional compatibility between plant hosts and AM fungi, the selection of appropriate isolates is a crucial step for effective mycorrhizal inoculation. We compared the growth response of bulbs of C. weedii var. intermedius that were inoculated with native AM fungi, a commercial mycorrhizal inoculum and sterile soil (nonmycorrhizal control).


Inoculation of intermediate mariposa lily bulbs with native AM fungi increased the proportion of plants that produced flowers, but the response was influenced by the bulb size.

The incorporation of native versus commercial mycorrhizal inoculum for rare plant propagation is discussed.