Effects of gamma radiation from cobalt60 on eggs and on 1st, 3rd, and last instars of Sitotroga cerealella (Olivier) were determined. Egg and larval sensitivity depended on age at treatment; the older the egg, the less susceptible. No egg hatched in the 0- to 12- and the 0- to 24-hour (hr) age groups when irradiated at 6 kr and 10 kr, respectively. Hatching was observed at all doses in the 24- to 48- and 48- to 72-hr age groups. Larvae failed to develop at doses of 10, 14, and 18 kr. After doses of 2 and 6 kr and controls, larvae developed normally. Irradiation of 1st, 3rd, and last instars resulted in reduced numbers, in delayed and incomplete emergence, and in structural deformities such as twisted wings and fusion of tarsal and antenna] segments. Females irradiated as 1st (18-24 hr and 4 days old), 3rd-, and last instars, then mated with normal unmated males or vice versa either laid infertile eggs or did not produce eggs at 14, 16, 17, and 20 kr, respectively. Emerged females following irradiation as last instars and mated with normal unmated males produced no eggs at 10 kr.
Document Type: Research Article
Publication date: August 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.