Rui Liu

College of Life Science,Hainan normal university，Haikou, 571158, Hainan, China
Author    Correspondence author
Molecular Entomology, 2025, Vol. 16, No. 1   
Received: 24 Dec., 2024    Accepted: 28 Jan., 2025    Published: 12 Feb., 2025

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

In this study, an artificial population of Asian corn borer (Ostrinia furnacalis) was established under laboratory conditions to provide the insect source required for Bt toxin bioassay. The initial insect source was obtained by collecting larvae and pupae from the field. Under the conditions of constant temperature of 26 ℃, relative humidity of 70%~90%, and photoperiod of 10 L: 14 D, the larvae were fed with fresh corn ears every day and their feeding and development processes were observed. It was observed that under laboratory conditions, it takes about 34~37 days for Ostrinia furnacalis to complete a generation. The average generation period of females is 36.2 ± 0.72 days, and that of males is 34.8 ± 0.72 days. The larval stage is 17-19 days, the pupal stage is 7-9 days, and the adult lifespan is 5-7 days. The larvae go through 5 instars, and the width of the head shell and the body length of each instar are significantly different. The investigation found that the feeding sites of larvae of different ages on corn plants were different. The second-instar larvae had a wider feeding range, while the older larvae mostly bored into the inside of the corn stalks to cause damage. In addition, the tolerance of larvae to Bt toxins increased with age. The established laboratory rearing method can efficiently cultivate consecutive generations of Asian corn borer, providing a standardized insect source for Bt toxin bioassay and resistance monitoring.

Asian corn borer; Laboratory rearing; Life history observation; Bt toxin; Bioassay