Submitted to: Journal of Entomological Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/27/1996
Publication Date: N/A
Citation: N/A Interpretive Summary: Corn earworm and fall armyworm are important pests of corn and several other agricultural crops in the U.S.A. The release of moths treated with substerilizing doses of irradiation to suppress the natural population of these pests by producing sterile progeny when they mate with the natural population is being considered as part of an integrated pest management strategy. Another control method being considered is the use on nuclear polyhedrosis viruses to kill pest larvae. The strategy of releasing moths irradiated with substerilizing radiation is dependent of the ability of the released insects and their progeny to survive and interact with the wild population. Thus, we wanted to determine if the progeny of irradiated moths are more susceptible to nuclear polyhedrosis viruses because that would imply that the two strategies are not compatible. Bioassays of progeny of irradiated moths revealed that they are not significantly more susceptible to virus infection than progeny of nonirradiated moths. Thus, the use of nuclear polyhedrosis viruses to reduce the number of larvae in the field should be compatible with the release of substerile moths in an integrated pest management program for area-wide management of the corn earworm or the fall armyworm.
Technical Abstract: Inherited sterility has been proposed as a means of suppressing the populations of the corn earworm, Helicoverpa zea (Boddie) and fall armyworm, Spodoptera frugiperda (J. E. Smith). If nuclear poly- hedrosis viruses could be used to kill larvae, thereby reducing the number of moths in field populations, fewer moths treated with substerilizing doses of irradiation would need to be released. However, for these two methods to be compatible the progeny of sub- sterile moths should be no more susceptible to the virus than the progeny of the field populations. The corn earworm nuclear poly- hedrosis virus (Elcar TM) was bioassayed against corn earworm larvae from untreated moths and larvae from male, female, and male and female moths treated with 100 Gy of irradiation and larvae from male moths treated with 150 Gy of irradiation. The fall armyworm nuclear polyhedrosis virus was bioassayed against fall armyworm larvae from untreated moths and larvae from male moths treated with 100 or 150 Gy of irradiation. There was no significant difference between susceptibility of larvae from untreated moths and larvae from irradiated moths. Thus, the use of nuclear polyhedrosis viruses for control of larvae should be compatible with release of substerilized moths as part of an integrated pest management approach for management of the corn earworm and the fall armyworm.