Institute of Agriculture, Iranian Research Organization for Science and Technology (IROST). Tehran, Iran. P. O. Box: 33535111. , atapour@irost.org
Abstract: (154 Views)
The overwintering conditions and cold tolerance of the Lime butterfly, Papilio demoleus L., are relatively unclear. In the present study, overwintering pupae were collected over several months, and changes in supercooling point (SCP), cold-hardiness, and body color were investigated. Also, some eggs were collected and reared in the laboratory, and then pupae were kept for 1-4 weeks at 0, 5, and 15 °C, and the changes in SCPs were studied. Shelters were prepared and installed in the field to check the overwintering sites. Also, the digestive tract was investigated before and at the beginning of the overwintering phase. The results showed that the SCP gradually decreased from -9 to -13 °C during the autumn months, and in lab-reared pupae treated at 0-5 °C, the SCP was reduced to -13 °C. None of the pupae survived at temperatures below the SCP, so this species uses a freeze avoidance strategy. As the weather gets cold, the color of most of the pupae (76.19%) tends to brown, while in the summer months, more than 80% of the pupae are green. The overwintering pupae emptied their ingested foods, and the contents of their digestive system before emptying contain Pseudomonas and Enterobacter species, both of which can act as ice nucleators. Ultimately, the relationship between these factors in adapting the pest to low temperatures was discussed.
Article Type:
Original Research |
Subject:
Insect Physiology Received: 2024/01/17 | Accepted: 2024/08/19 | Published: 2024/08/24