Oviposition Preference of Spodoptera latifascia (Lepidoptera: Noctuidae) for Sorghum, Maize and Non-Crop Vegetation
Oviposition preferences of Spodoptera latifascia (Walker) (Lepidoptera: Noctuidae) for sorghum [Sorghum bicolor (L.) Moench (Poaceae)], maize [Zea mays (L.) (Poaceae)], and various non-crop species were examined in field cage experiments. A higher percentage (pooled means) of the total number of eggs per plant were laid on Amaranthus sp. (probably A. hybridus L. or A. viridis L.) (Amaranthaceae) 24%, maize 32%, and Ixophorus unisetus (Presl.) Schlecht (Poaceae) 26%, than on Ipomoea sp. [(probably I. purpurea (L.) Jacq.] (Convolvulacea) 2%, Melampodium divaricatum (Rich. ex pers.) Dc. (Asteraceae) 6%, Portulaca oleracea L. (Portulacaceae) 7%, and sorghum 3%. Only maize had a significantly higher percentage of the total number of eggs laid per plant than the other plant species in one of two experiments. Plant growth stage (seedling vs. older) did not appear to influence oviposition on any of the plant species tested. Moths exhibited a wide host oviposition range in our cage experiments. In contrast, eggs were collected only from Amaranthus sp., I. unisetus, and maize in the field in southern Honduras, suggesting that S. latifascia oviposition response in nature may be somewhat restricted to certain non-crop species and maize. Our data support results from previous investigations revealing the potential benefits of non-crop host plants in reducing damage by S. latifascia to sorghum and maize in intercropped production fields during the early growing season in southern Honduras.