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Biological pest control agents


An experimental Integrated Pest Management (IPM) program was developed to reduce the use of pesticides m me greenhouses at the University of Minnesota, Morris. Six predatory or parasitic insect species were released to control populations of aphid, scale, mealybug, thrips, whitefly, and spider mite. Beneficial insect populations were supplemented several times. Pest and beneficial insect populations were monitored weekly for one' year. No pest species were eliminated but all except scale were effectively controlled. Aphid and whitefly control was effective within the first two months; control of the other pest insects took from 5 to 6 months to a year. All pest insect population densities other than spider mite attained maxima at separate times during the year and each beneficial insect population tended to attained a maximum slightly after its host or prey population. The program is cost effective and additional greenhouse employees are being instructed so the program can be continued.

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Entomology Commons



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