Comparative Evaluation of Development and Reproductive Capacity of Two Biotypes of Lilioceris cheni (Coleoptera: Chrysomelidae), Biological Control Agents of Air Potato (Dioscorea Bulbifera) in Florida

Authors: MANRIQUE, VERONICA - University Of Florida; Lake, Ellen; Smith, Melissa; DIAZ, RODRIGO - University Of Florida; Franko, Carly; Pratt, Paul; Rayamajhi, Min; OVERHOLT, WILLIAM - University Of Florida

Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2016
Publication Date: 2/22/2017
Citation: Manrique, V., Lake, E.C., Smith, M., Diaz, R., Franko, C., Pratt, P.D., Rayamajhi, M.B., Overholt, W.A. 2017. Comparative Evaluation of Development and Reproductive Capacity of Two Biotypes of Lilioceris cheni (Coleoptera: Chrysomelidae), Biological Control Agents of Air Potato (Dioscorea Bulbifera) in Florida. Annals of the Entomological Society of America. 110(3):310-316.

Interpretive Summary: A Chinese biotype of Lilioceris cheni Gressitt and Kimoto (Coleoptera: Chrysomelidae) is being mass reared and released in Florida for control of the invasive vine, Dioscorea bulbifera L. (Dioscoreales), air potato. Another biotype from Nepal is under investigation to determine if its release would benefit the ongoing biological control program. We compared temperature dependent development, fecundity, life table parameters, and consumption of the two biotypes in the laboratory. Beetles from both biotypes completed development at 20 – 30 °C, although survival of Chinese beetles was higher at 20 °C and 27.5 °C, and survival of Nepalese beetles was higher at 30 °C. Nepalese beetles developed at a faster rate at 20 °C, and consumed air potato foliage at a higher rate at 25 °C. Fecundity was much higher in the Chinese biotype. However, the shorter generation time of the Nepalese beetles resulted in a higher intrinsic rate of population increase. This may allow a more rapid population increase of Nepalese beetles in the field, and thus, greater damage to air potato plants. However, differences in other life history traits, such as overwintering ability, diapause, and cold tolerance, will also influence field performance.

Technical Abstract: A Chinese biotype of Lilioceris cheni Gressitt and Kimoto (Coleoptera: Chrysomelidae) is being mass reared and released in Florida for control of the invasive vine, Dioscorea bulbifera L. (Dioscoreales). Another biotype from Nepal is under investigation to determine if its release would benefit the ongoing biological control program. We compared temperature dependent development, fecundity, life table parameters, and consumption of the two biotypes in the laboratory. Both completed development at 20 – 30 °C, although survival of Chinese beetles was higher at 20 °C and 27.5 °C, and survival of Nepalese beetles was higher at 30 °C. In addition, Nepalese beetles developed at a faster rate at 20 °C, and consumed air potato foliage at a higher rate at 25 °C. The most important difference between the biotypes, in regards to biological control purposes, was the shorter generation time of Nepalese beetles, which resulted in a higher intrinsic rate of population increase, despite much higher fecundity of Chinese beetles. The higher intrinsic rate of increase of the Nepalese beetles may allow a more rapid population increase in the field, and thus, greater damage to air potato plants. However, differences in other life history traits, such as overwintering ability, diapause, and cold tolerance, will also influence field performance.