Relative Cabbage Consumption by the Cabbage Looper (Lepidoptera: Noctuidae), Beet Armyworm (Lepidoptera: Noctuidae), and Diamondback Moth (Lepidoptera: Plutellidae)

In a laboratory feeding study, larvae of the diamondback moth, Plutella xylostella (L.); beet armyworm, Spodoptera exigua (Hübner); and cabbage looper, Trichoplusia ni (Hübner), consumed a mean of 0.13, 1.53, and 4.27 g of cabbage foliage per larva, respectively, during their larval development. The consumption ratio for the diamondback moth, beet armyworm, and cabbage looper based on mean consumption per larva was 1:11.8:32.8. The diamondback moth, beet armyworm, and cabbage looper took a mean of 14.2, 39.3, and 25.7 d, respectively, to complete larval development at 25 ± 1°C. The consumption ratio for the three species, as listed, based on mean consumption in grams per day, was 1:4.3:18.4.