The 2008 Joint Meeting of the Society for Range Management and the America Forage and Grassland Council. |
Monday, January 28, 2008
36
Mycorrhizal Associations of Fremontodendron Californicum from California and Arizona
Theresa L. Price and Jean Stutz. Applied Biological Sciences, Arizona State University Polytechnic, 7001 E. Williams Field Road, Mesa, AZ 85212
Chaparral plant communities are known to have plants with more than one type of mycorrhizal association including arbuscular mycorrhizal, ectomycorhizal and non-mycorrhizal plants, but there have been few investigations of the mycorrhizal relationships of chaparral plant species within the Malvacaeae. We examined the mycorrhizal status of Fremontodendron californicum, a chaparral shrub within the Malvaceae (s.l.) found throughout California , Baja (Mexico ), and central Arizona . This species is a short-lived shrub found growing in areas of disturbance, especially disturbances due to fire and browsing. While in California this shrub is somewhat abundant in the areas of natural occurrence, the Arizona plants exhibit a scattered distribution throughout central Arizona with few plants at each locality. It is hypothesized that the mycorrhizal associations of this shrub are different between the two geographic areas in this study. Differences in the mycorrhizal relationship may explain the limited distribution of the Arizona species. Root samples from two populations of F. californicum from the San Gabriel Mountains of southern California and one Arizona population from Mt. Ord were collected and assessed for root colonization by ectomycorrhizae and arbuscular mycorrhizae. Results from this study will serve to give a preliminary idea of the type of mycorrhizal associations of F. californicum and also indicate the relevance of root mycorrhizal associations as a possible factor contributing to the limited distribution of F. californicum in Arizona .