Two field applications of 10 or more Heliothis zea (Boddie) eggs at intervals of 0-10 days or a single appli- cation of at least 30 eggs produced damage to corn comparable to that produced by any method of larval in- festation tested. Repeated applications were more important than number of eggs per application in producing results comparable to current larval infestation methods. Under low natural infestation, the percentage of infested cars was substantially increased by a single application of eggs, but was still less than the artificial larval infestation. Differences among hybirds in their response to levels of infestation were attributed largely to a greater percentage of escapes (ears that escaped damage) for certain hybrids, because the interaction between hybrids and infestation levels disappeared when infestation percentages among hybrids were uniform. The effect of timing or number of applications was quite constant among hybrids when the number of escapes was not a factor. Practical aspects of substituting egg- infestation for the conventional method of larval infestation are discussed.
Document Type: Research Article
Publication date: April 1, 1970
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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.