Role of photoperiod in the development and reproduction of Harmonia axyridis (Coleoptera, Coccinellidae)

ABSTRACT

To improve the laboratory mass rearing and the winter greenhouse use of the multicoloured Asian lady beetle Harmonia axyridis (Pallas) (Coleoptera, Coccinellidae), the effects of photoperiod on the development and fecundity of H. axyridis were investigated at 20°C and photoperiods ranging from 0L:24D to 24L:0D. We foun'd photoperiod to significantly affect the pre-imaginal development and reproduction of H. axyridis. The development of the pre-imaginal stage was significantly faster at shorter photoperiods (0–14 h) than at longer ones (16–24 h). The proportion of females laying eggs within the first 30 days after eclosion, the mean number of eggs per ovipositing female, and the long axial length of the first oocyte were all lower at shorter photoperiods (6–12 h) than at longer ones (14–24 h). These results suggest that adult H. axyridis may encounter problems in preying and reproducing in the winter conditions of unheated and unilluminated greenhouses in areas with temperatures lower than 20°C and day lengths shorter than 12 h.

KEYWORDS:

• Harmonia axyridis photoperiod
• development
• reproduction

Acknowledgements

We would like to thank the editor and anonymous reviewers for valuable comments and suggestions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under grant numbers 31201542 and 31272095 as well as the Hebei Nature Science Foundation of Higher Education Institutions for Youth under grant number Y2012011.