Submitted to: International Institute For Beet Research Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/5/1997
Publication Date: N/A
Interpretive Summary: The sugarbeet root maggot has been recognized as a serious insect pest of sugarbeet in North America since the 1920s. Feeding damage reduces stands and root yields. We have identified a fungal pathogen which attacks and kills all stages of this insect. This pathogenic fungus is equal to or better than the insecticides which are now used for control and thus mayu prove to be an effective replacement.
Technical Abstract: The sugarbeet root maggot (Tetanops myopaeformis) is a serious insect pest of sugarbeet in North America. Larvae feed on developing sugarbeet by tunneling along the root surface. Feeding causes yield loss by reducing stands early in the season and/or reducing root yields at harvest. Insecticide applied at planting is the primary control method. One resistant line, F1015, was released to breeders in 1996. Sugarbeet root maggot damage to F1015, as evidenced by the number and size of feeding scars is substantially less for any commercial hybrid tested. The entomopathogenic fungi Metarhizium anisopliae has been the most successful root maggot biocontrol agent we have identified, to date. Damage ratings and yield data from two environments indicate that a fall (preceding planting) plus spring (planting time) application of fungi provides better control than a single application either spring or fall.