Quantitative survivorship analysis of the velvetbean caterpillar (Lepidoptera: Noctuidae) pupae in soybean fields in Louisiana.

Seven species of insects including ground beetles, tiger beetles, earwigs, and the red imported fire ant, Solenopsis invicta Buren, were identified in laboratory feeding trials as pupal predators of velvetbean caterpillar, Anticarsia gemmatalis Hubner. The survivorship and predation of velvetbean caterpillar pupae were studied in soybean fields in Louisiana. Two descriptive categories of predatory feeding action were identified, “partial” and “complete”. Predation was the principal mortality factor, accounting for 52.5 to 95.2% mortality in plots with fire ants. The red imported fire ant was a primary predator, accounting for 77.5 to 96.5% of total predator mortality for pupae under the soil surface in plots with fire ants. Our studies also indicated that the red imported fire ant seemed to reduce other ground-dwelling pupal predators of velvetbean caterpillar.