University of Arizona
ARIZONA AFLATOXIN AF36 PROGRAM
* Aflatoxins are carcinogenic toxins/by-products produced by various strains of a common fungus (Aspergillus flavus). For over thirty
years, aflatoxins have cost Arizona’s cotton producers annual losses of over $5 million. Cottonseed containing over 20 parts per
billion of aflatoxin cannot be fed to dairy cows, and results in $20-$50 per acre loss in revenue. Pictured left: Raw wheat on the left and
after innoculation (sporulated) on the right.
* Several key U.S. trading partners strictly regulate aflatoxins. Crops with even very low aflatoxin contents may be at a severe
* Aflatoxins also contaminate corn, peanuts and several tree crops including almonds, pistachios and figs.
* Pioneering research conducted by Dr. Peter Cotty, USDA ARS, identified certain native strains of Aspergillus flavus which do
not produce aflatoxin, occur naturally in the southwestern deserts but at very low levels.
* One of these atoxigenic (non-toxin producing) strains, Aspergillus flavus AF36, has been shown to competitively displace
aflatoxin-producing strains when applied to cotton fields. This displacement is associated with reduced aflatoxin levels in
* Aspergillus flavus AF36 was evaluated in commercial fields in Yuma, Arizona, during the period of 1996-1998. The results
suggested a high potential for reducing the vulnerability of all crops grown in a treated region to aflatoxin contamination. This
provided the opportunity for an areawide aflatoxin management or suppression program.
* The Arizona Cotton Research & Protection Council (ACRPC) established a working partnership with USDA ARS and Dr. Cotty
to both manufacture AF36 and advance atoxigenic strain technology.
AF36 PRODUCT REGISTRATION
In June 1998, the ACRPC applied for both experimental use and Section 3 registration with EPA for AF36. Full Section 3 registration was granted by the EPA in November, 2007.
USDA ARS LICENSING
In August 1998, USDA ARS granted ACRPC a non-exclusive royalty-free license to utilize USDA atoxigenic strain patents to control aflatoxin in Arizona cotton.
MANUFACTURING FACILITY DEVELOPMENT
In September 1998, the ACRPC leased 15,000 square feet of building/warehouse space to house a prototype AF36 production facility plus associated labs and offices. Facility development has progressed to its current state which is capable of supplying commercial scale quantities of AF36 capable of treating more than 120,000 crop acres per season. This represents a multi-million dollar investment on the part of the Arizona cotton industry.
Since its inception in 1999, the USDA ARS / ACRPC partnership has led to the treatment and evaluation of AF36 applications on more than 120,000 cumulative acres of cotton in Arizona and Texas. This, in turn, has resulted in the progressive displacement and hence reduction of aflatoxin producing fungi by AF36 throughout treatment regions. Refinements continue in the production, distribution and utilization of atoxigenic strain technology with the ultimate goal of transfer of said technology to other grower organizations and commodity groups. This process is accelerated through coordinated basic and applied research involving the Arizona Cotton Research & Protection Council and USDA ARS.
The expansion of atoxigenic strain technology to a wide variety of agricultural commodities holds great potential for the future. Current cooperative research focusing on corn, pistachios and figs coupled with existing registrations for cotton in the West offers hope for a bio-control technology which may significantly enhance the agricultural export market for the United States while concurrently addressing critical issues of public health and safety.
The current research partnership between Dr. Peter Cotty, USDA ARS, and the Arizona Cotton Research and Protection Council represents a model for cooperative development of public sector technology which has multiple applications across agricultural commodity lines. Continued USDA ARS support of this mutually beneficial working relationship is strongly encouraged by cotton industry groups in both Arizona and Texas.
This page was modified January 03, 2008