Biopesticides - Pesticides: Evaluation of Environmental Pollution - page 601

Pheromones (Gk. phereum , to carry; horman , to excite or stimulate) are released by one
member of a species to cause a specific interaction with another member of the same spe-
cies. Pheromones may be further classified on the basis of the interaction mediated, such as
alarm, aggregation, or sex pheromone. It is the sex pheromones of insects that are of particu-
lar interest to agricultural integrated pest management (IPM) practitioners. The first insect
sex pheromones were identified in the late 1950s and initially were scientific curiosities.
Kairomones are also members of the group of semiochemicals where the signal detected
is beneficial to the perceiving species. For example, a mountain pine beetle attacks pine
trees and not alder trees because it recognizes both the kairomones of appropriate hosts
and nonhost species.
19.11 Conclusion
Effective biopesticides are similar to chemical pesticides and work with good efficacy
against the pest for which they are labeled. There has been considerable consumer and
governmental pressure to minimize the use of chemical pesticides. This can be seen by
the desire of the consumer to purchase organic produce and by supermarkets demanding
that growers utilize environmental sensitive crop production strategies. The unique value
for biopesticides is based on the three “R's”: resistance management, restricted entry inter-
vals, and residues. Since biopesticides have multimodes of action, there is less chance of
developing resistance in a particular insect. They can be an excellent component of an inte-
grated pest management (IPM) program. Restricted entry intervals (REIs) determine the
timing of application relative to a number of factors. The majority of biopesticides have low
REIs, mostly around 0-4 h with no preharvest interval. After a biopesticide is applied, a
farmer can go into the field and harvest immediately. Residues are a regulatory issue with
pesticides. Since biopesticides tend to pose fewer risks compared to conventional chemical
pesticides, the EPA generally requires less data to achieve new product registrations (<1
year). Conventional chemical pesticides can take up to 3 years for regulatory approval. The
cost of registration of a biopesticide product is usually an order of magnitude less than for
a chemical pesticide product. In the United States, the cost of registration of a biopesticide
can usually be measured in hundreds of thousands of dollars. By contrast, registration of
a chemical pesticide costs millions of dollars. This reflects the regulator's preference for
biopesticides, especially Bt products. Because of high chemical registration costs, many
high-value crop and niche markets are now being left without effective chemical crop pro-
tection solutions, leaving Bt as the economical choice for many producers.
References
AgriDyne Technologies, Inc. 1994. Greenhouse Grower . Floritech report: Tough on pests, easy on
crops—And the environment. AgriDyne Technologies, Inc.: Salt Lake City, UT.
Anonymous. 1981. Semiochemicals: Their role in pest control. In: Nordlund, D. A., Jones, R. L., and
Lewis, W. J. (eds), 306 p. John Wiley & Sons: New York.
Antonious, G. F. 2004. Residues and halflives of pyrethrins on field-grown pepper and tomato. J.
Environ. Sci. Health B39: 491-503.