Biology of Dichomeris famulata Meyrick, 1914 (Lepidoptera: Gelechiidae) in maize

Abstract

The caterpillar Dichomeris famulata Meyrick, 1914 (Lepidoptera: Gelechiidae) is a new pest of corn ear in Brazil, and its study is important in seed fields. The aim of this was to study the biology of this pest under laboratory conditions (25±2°C, 65±10% of RH and 14-hours of photophase). The biological cycle (egg-adult) was of 35.2 days. The incubation period was of 4.1 days. The average larval development time was of 21.1 days, and 5 instars were observed. The pupal period was of 8.4 days and the pupae weight was of 12.4 and 11.3 mg for males and females, respectively. The females laid an average of 118 eggs with a pre-oviposition period of 10.7 days and an oviposition time of 14.0 days. The mean longevity of males and females was of 37.02 and 44.16 days, respectively, and sex ratio was of 0.48. The caterpillars damage the silks and grains at the milk stage through little entry orifices, damaging the endosperm and, more importantly, the embryo, reducing the seed germination. These results can support the establishment of strategies to manage this new corn ear pest, especially in seed fields.