Submitted to: Almond Industry Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/30/2008
Publication Date: 12/1/2008
Citation: Hua, S.T., Browne, G.T., Ledbetter, C.A. 2008. Innoculation of Almond Rootstock with Symbiotic Arbuscular Mycorrhizal Fungi. Almond Industry 2008 Conference Proceedings. p.91-94. Interpretive Summary: There is very limited research being conducted on using AM mycorrhizal fungi to improve almond root system. Numerous research publications have documented the beneficial AM symbiotic association with roots including mineral nutrition uptake enhancement, disease resistance and water stress tolerance. AM fungal spores were produced for inoculating almond rootstocks for field trial in February, 2008. Evaluation of almond tree performance is in progress. The study also indicates fumigation reduced natural soil population of AM fungi in almond orchard.
Technical Abstract: In August 2007 root samples were collected from an existing fumigation plot in which trees were planted January 2007. Trap cultures of Sudan grass were established to multiply the residual AM fungus. A special nutrient medium was applied to irrigate Sudangrass for boosting AM innoculum production. AM spores were produced in January 2008 and used to inoculate almond rootstocks planted in February 2008. Roots of Sudan grass from trap cultures were analyzed for AM fungal colonization by fumigated and non-fumigated soils. Five hundred and fifty root fragments (I cm long) were stained with trypan blue and scored for colonization. 60% roots from non-fumigated soil were colonized. About 40% of the roots from fumigated soil were colonized. The data indicate that fumigation did reduce residual soil AM population. Preliminary results indicate that Glomus Mosseae, Glomus 3, Gigasproa rosea, Glomus intraradices were present in the soil and in colonized roots.