Quantifying Pepper Maggot (Diptera: Tephritidae) Oviposition and Infestation Over Time

Abstract

In 1998 and 1999, pepper maggot flies, Zonosemata electa (Say), were excluded from pepper plants with row covers for 0-6 wk after initial oviposition was detected. The proportion of oviposition attempts (scars) and larval infestation that occurred each week and the cumulative oviposition and infestation over time were determined. Due to environmental factors, initial oviposition was delayed, and the numbers of oviposition scars on fruit and flies caught on traps were lower in 1998 than in 1999. The proportions of scarred or infested fruit were low (< 8% of total) during the first 7 d after the pest was detected each year. Oviposition peaked 8-14 d after beginning in 1998, but not until 21-28 d after the initial scar was detected in 1999. Because systemic insecticides tend to provide control of adults and most hatching larvae, it may be possible to delay the initial insecticide application for up to a week after oviposition commences and still minimize fruit damage. There was no association with either year between the proportion of flies captured on traps and the proportion of oviposition scars on fruit the same week or 1 and 2 wk later.