During the growing season of 1977 , field studies were conducted to determine the damage density relationships resulting from artificial infestations (1 larva/plant) of Heliothis virescens (F.) on Maryland tobacco. It was found that yield and quality reductions were negatively correlated with larval density, while plants were able to compensate for some foliar loss throughout most growth stages. Compensation was highest during growth periods of rapid meristematic activity. Sensitivity to defoliation was most evident during root formation and production of floral parts, although markedly less during the latter. Theoretical economic injury levels (EIL's) for the tobacco budworm were determined by integrating several economic parameters with value-density relationships. EIL's indicated that throughout most developmental stages of MD. 609 tobacco large populations of budworms can be tolerated without sufficient damage to warrant suppression. Under Maryland conditions, economic thresholds of 25% infestation densities would better approach optimal benefit-cost relations than the current 10% level.
Document Type: Research Article
Publication date: June 1, 1980
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.