The temperature threshold and thermal requirements for total development (egg through 50% moth emergence) of Hydraecia immanis Guenee were determined under controlled conditions. Developmental rate was linearly related to temperature (12.8-23.9°C). The threshold temperature, regression equation, coefficient of determination (r2), and degree days (DD) for total development were 5.3°C, y = 0.057x - 0.303, r2 = 0.99, and 1,756.8, respectively. Seasonal flight of H. immanis was monitored with blacklight traps during 1982- 1984 at Lanark, Ill., and cumulative emergence was related to degree-days. Over the 3-yr study, first capture of moths began when an average of 1,324.4 DD had accumulated; 50% moth capture coincided with an average of 1,762.0 DD. A logistic regression model gave projected degree-day requirements of 1,471.2 for 10% and 1,726.9 for 50% catch. Calendar date estimates were considerably less accurate than either cumulative degree-days or regression equation methods for predicting published 10 or 50% moth flight at two sites in Wisconsin. The regression model predicted 10% moth flight within 1 to 3 d, depending on site. Only 19 of the 222 moths captured during the 3-yr period were female, whereas 14 of 21 fieldcollected larvae reared to the adult stage were female. Seventeen of the 19 females captured in the 3-yr study were mated, and the reproductive status of these females was classified as ovipositional.
Document Type: Research Article
Publication date: April 1, 1989
More about this publication?
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.