ABSTRACT
The bollworm, Helicoverpa zea (Boddie), and the tobacco budworm, Heliothis virescens (F.), were responsible for $48,497,700 in associated crop losses and insecticide costs in Texas cotton in 1995 (Williams 1996). Current tactics for bollworm/budworm control place an emphasis on monitoring pest densities in individual fields and initiation chemical control measures when an economic threshold is reached (Knutson et al. 1994). Several studies have commented on the impact of natural enemies on the survivorship of bollworm/budworm eggs and first instar larvae in cotton, but few have provided quantitative estimates of mortality. Parasitization and impact of pathogens can be quantified by rearing the hosts, but predators are more difficult. A study was initiated to construct partial ecological life tables of bollworm in cotton in the southern Blacklands and develop an immunoassay to determine the impact of the numerically dominant egg predator.
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