Differences in the link between female moth oviposition and larval fitness in Grapholita molesta (Lepidoptera: Tortricidae) over seasonal variation of host fruit species

Abstract

Oriental fruit moth (OFM) is a cosmopolitan borer pest. Adults migrate among peach, pear or apple orchards. However, the association of female oviposition with larval fitness over seasonal variation of fruit species have not been reported. This study investigated female oviposition and larval fitness during four sampling months of peach, apple and pear related with maturity. Infested fruits were investigated in three orchards. These results showed that females laid fewer eggs on apple than peach or pear in June and July, but not May and August. Fitness index of larvae on pear was lower than peach or apple in May, June and August, except for July. In June, larvae failed completely to bore into pear. The ranking of infestation ratio was peach orchard (from June to July) > pear orchard (July onward) > apple orchard (late June onward). Based on the above results, peach (June and July) and pear (July and August) were more suitable than apple (June, July and August), whereas peach (May), apple (May) and pear (May and June) were unsuitable for OFM.

Keywords:

• Grapholita molesta
• female oviposition
• larval fitness
• association between female moth oviposition and larval fitness
• host plant

Acknowledgments

The authors would like to thank Ms. Rui-Qing Ma for help during the experiments.

Disclosure statement

The authors declare that there is no conflict of interest.

Additional information

Funding

This study was funded by the Earmarked Fund for CARS (CARS-28), the National Guides Local Science and Technology Development Fund Projects (YDZJSX2022C026; YDZJSX2022A034), the Shanxi Agricultural University Fund for Doctors (2021BQ54), the Supported by Fundamental Research Program of Shanxi Province (20210302124517) and the Supported by Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (2021L100).