# Development of the Citrus Longhorned Beetle Anoplophora chinensis (Cerambycidae: Coleoptera) on Artificial Diet and Chilling Effect on Their Life Cycle Completion

## TL;DR

Researchers found that chilling Anoplophora chinensis larvae at specific temperatures and durations improves their pupation success when reared on an artificial diet.

## Contribution

The study introduces optimized chilling regimes and artificial diet protocols for successful laboratory rearing of Anoplophora chinensis.

## Key findings

- Pupation success increased with longer chilling periods, reaching 55% after 16 weeks at 10 °C.
- Developmental durations ranged from 34 to 89 weeks depending on the number of chilling cycles.
- Adults reared on artificial diet had significantly lower body weight compared to field-collected individuals.

## Abstract

This study examined how cold treatment (chilling) affects the development of Anoplophora chinensis larvae reared on an artificial diet and their life cycle completion. Larvae were exposed to low temperatures (5 °C and 10 °C) for various durations and then returned to warm conditions to monitor pupation. Results showed that longer chilling periods increased pupation success: 55% pupated after 16 weeks at 10 °C, compared with 16.7% after 12 weeks and none after 9 weeks. Some larvae required one to three chilling cycles to complete their life cycle, with development times ranging from 34 to 89 weeks. The body weight of adults emerging from the artificial diet was significantly lower than those collected in the field. Overall, the study demonstrates that both chilling duration and temperature are critical for successful pupation, offering insights that may support scalable rearing of this species under laboratory conditions.

Anoplophora chinensis (Coleoptera: Cerambycidae) is an invasive, economically important, quarantined wood-boring pest whose long-life cycle complicates laboratory rearing and management. This study investigated the combined effects of artificial diet, chilling duration, and temperature on pupation cues. Adults collected from the wild were allowed to oviposit, and newly hatched larvae were reared on a prepared artificial diet. Larval weight was recorded biweekly to assess growth and mortality. At 12 weeks of age, larvae were subjected to cold treatments at 5 °C or 10 °C for 9, 12, 14, 16, or 19 weeks, then returned to warm rearing conditions to monitor pupation. Additional chilling cycles were applied when necessary. Pupation percents increased with chilling duration, reaching 55% after 16 weeks at 10 °C compared with 16.7% after 12 weeks and none after 9 weeks. Developmental durations were 34.43, 55.93, and 88.65 weeks for larvae experiencing one, two, and three chilling cycles, respectively. Adults body weight was consistently lower than that of field-collected individuals for both males and females. These findings confirm that chilling is essential for pupation cues and demonstrate that both duration and temperature strongly influence pupation success. Importantly, the combination of artificial diet with optimized chilling regimes enhances pupation rates, providing a practical foundation for mass-rearing protocols of A. chinensis to support future research and management programs.