Theses and Dissertations Collection

The sugar beet root maggot, Tetanops myopaeformis (Diptera: Ulidiidae), is a major pest of sugar beet in the United States and Canada. Current management practices are heavily reliant on chemical control. However, insecticides commonly used against T. myopaeformis are being phased out of use, necessitating alternative management approaches. A primary objective of this study was to develop protocols for rearing a laboratory colony of T. myopaeformis, especially for use in host resistance screening assays. Adults reared from field-collected larvae were used to examine the modality of resistance of a known resistant sugar beet variety. Paired-choice tests showed no difference in oviposition rates between a susceptible and resistant variety whereas no-choice tests showed greater feeding damage and larval numbers on the susceptible variety. For the resistant variety, antibiosis was the putative modality of resistance. Our protocols can be used to expedite the process of developing varieties with resistance to T. myopaeformis.