The cooperation with the University of California, Davis started when Dr. Christos Vasilikiotis, Associate Professor at Perrotis College and Chair of the Sustainable Agriculture & Management B.Sc. program visited the university in Spring 2016. In September 2018, he collaborated with Dr. Amélie Gaudin from the Department of Plant Sciences, College of Agricultural and Environmental Sciences for a research project and published their paper “Orchard Management Practices Affect Arbuscular Mycorrhizal Fungal Root Colonization of Almond” in the Biological Agriculture and Horticulture scientific journal.
The research project evaluated a variety of soil management practices in almond production in California, in both organic and conventional farm settings. Almond orchards are rapidly expanding across California (which accounts for 80% of world almond production), where common management practices such as year-long bare orchard floors, agrochemical use, and synthetic fertilizer inputs are degrading soil ecosystems and the services they provide. The need is growing for management strategies that improve soil ecological function and biodiversity to help reduce the environmental and water footprint of almond production.
Almond trees can form a symbiotic relationship with mycorrhizae, a type of fungus which allows plants a greater access to soil moisture and various nutrients. When mycorrhizae are present in soil, they defend against pathogens, absorb water and phosphorus and carry nutrients to the roots of the almond trees. A large-scale survey of almond orchards in the Central Valley of California was conducted to determine the extent of mycorrhizal associations with roots and the impact of orchard management practices and soil properties on mycorrhizal root colonization rates.
The results showed a ubiquitous presence of mycorrhizae in commercial almond orchards, but mycorrhizal root colonization was higher in organically managed orchards than in conventionally managed ones. In addition, mycorrhizal root colonization improved in the presence of a soil vegetative cover on the orchard floor (cover crops). These results can help guide farm managers in selecting soil management practices, particularly the use of cover crops that increase the sustainability (more efficient input use for irrigation, nutrients and reduced pesticide use) of almond production.
BACK
