long-term value of viral approaches for widespread use has not been demonstrated.
Helicoverpa zea Boddie (cotton bollworm) nuclear polyhedrosis virus (NPV) was the first baculovirus to be marketed in the United States. It was developed by International Minerals and Chemical Corporation (IMC) but marketed by Sandoz under the tradename Elcar in 1976 after purchase of IMC 's biological products division. Interest in Elcar declined with the introduction of pyrethroids, which are effective, inexpensive broad-range insecticides. The properties of viruses suitable for IPM systems have been well studied (Ignoffo and Garcia 1992).
In Europe, a number of companies—including Kemira Oy (Finland), Oxford Virology (United Kingdom), and Calliope (France)—have introduced viral products for the insecticide market or are developing them. Viral products include Cydia pomonella L. (codling moth) granulosis virus (GV), Neodiprion sertifer (Geoffrey)(European pine sawfly) NPV, Spodoptera exigua (Hübner)(beet armyworm) NPV, and Autographa californica (Speyer) (alfalfa looper) NPV. The largest use of baculoviruses is in Brazil, where Anticarsia gemmatalis Hübner (velvetbean caterpillar) NPV protects 5.9 million hectares of soybeans against the velvetbean caterpillar.
In North America, the effort with baculoviruses has been led mainly by government agencies (Cunningham 1988, Podgwaite et al. 1991, Otvos et al. 1989). The US Forest Service (USFS) has registered NPVs to control Lymantria dispar (L.) (gypsy moth), Neodiprion sertifer, and Orgyia pseudotsugata (McDunnough) (Douglas fir tussock moth) in forestry. The Canadian Forest Service holds registrations for O. pseudotsugata NPV and Neodiprion lecontei (Fitch) (redheaded pine sawfly) NPV. US companies actively involved in baculovirus research are American Cyanamid, Thermo Trilogy, and DuPont.
Louis Falcon (University of California, Berkeley) has demonstrated the successful use of codling moth granulosis virus in pear, apple, and walnut IPM systems in California and Washington (personal communication, May 12, 1991). Organic growers pay $30 per acre-treatment of virus and make applications five to 10 times per season, in contrast with conventional growers who spray monthly (three times per season) the organophosphate insecticide Guthion™ at $7.50-10.00 per acre-treatment. According to Falcon, the cost of total chemical inputs (insecticides, fungicides, acaricides, bactericides) is approximately $360 per season and the total cost of all pesticides (fungicides, miticides, insecticides), including the virus for codling moth is $316 per season. In the virus-treated orchards, natural enemies can survive to control mite pests, thus eliminating the need for miticides, which are required in Guthion-treated orchards. Although Dr. Falcon's program has been successful for organic growers, mainstream fruit producers have not switched to it, because