Anaerobic soil disinfestation

Jul 28, 2009

Ventura County UCCE Staff Research Associate Maren Mochizuki shares current research which hopes to provide an organic method to kill plant pathogens and weed seeds in production agriculture.

Synthetic chemicals to fumigate soil have been used in some production agricultural systems, to kill plant pathogens and weed seed before planting crops.  Here in Ventura County, this is a common practice for strawberry production.  Joji Muramoto, Associate Researcher at UC Santa Cruz and Oleg Daugovish, Ventura County UCCE Farm Advisor and Maren Mochizuki, Ventura County UCCE Staff Research Associate are investigating an organic method to treat soil before planting by creating anaerobic, or oxygen-free, conditions.  Most organisms, including plant pathogens, cannot survive without oxygen.

We incorporated rice bran from the Central Valley into the soil as a carbon source to trigger microbial activity.  To test the applicability within a strawberry production system, we created planting beds topped with plastic mulch.  The beds needed to be well-sealed to ensure no air leaks that could add oxygen.  Using drip irrigation, we added sufficient water to the beds to fill all soil pores, further pushing out any air/oxygen.  Each day we monitor the soil environment with sensors measuring soil water content, temperature, and the level of anaerobic conditions and add more water as needed.  At the end of three weeks, we will evaluate the survival of a significant plant pathogen, Verticillium dahliae.

 

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ASD Sensors

 

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ASD beds