# Intake of Pyriproxyfen Through Contaminated Food by the Predator Ceraeochrysa claveri Navás, 1911 (Neuroptera: Chrysopidae): Evaluation of Long-Term Effects on Testes via Transcriptome Analysis

## TL;DR

This study shows how exposure to the insecticide pyriproxyfen during the larval stage of a beneficial green lacewing can affect gene expression in adult testes, potentially impacting reproduction.

## Contribution

The study introduces a novel transcriptomic approach to assess long-term sublethal effects of pyriproxyfen on a non-target insect.

## Key findings

- Exposure to pyriproxyfen during the larval stage altered gene expression in adult testes.
- A total of 46 to 64 differentially expressed genes were identified across the three treatment comparisons.
- Four specific genes (BPHL, Large2, MLX, and Talin-1) were validated as affected by pyriproxyfen exposure.

## Abstract

The green lacewing, Ceraeochrysa claveri, is an insect commonly utilized in integrated pest management (IPM) programs due to its predatory behavior during the larval stage, which helps control populations of pest insects. Understanding the sublethal effects of insecticides on non-target insects is crucial for effective IPM. This study aimed to evaluate the impact of pyriproxyfen on the gene expression in the testes of adult C. claveri exposed to insecticide during the larval stage. The larvae were fed Diatraea saccharalis eggs treated with pyriproxyfen for 10 days. After this, the larvae were fed untreated eggs until pupation. The testes from the adults were then extracted for molecular analysis. A transcriptome assembly was performed to identify differentially expressed genes (DEGs) between the three treatments analyzed. A total of 46 DEGs were identified in the first comparison, 47 DEGs in the second comparison, and 64 DEGs in the third comparison. Four genes (BPHL, Large2, MLX, and Talin-1) were selected for validation. The results indicated that the exposure of C. claveri larvae to pyriproxyfen could alter the gene expression and lead to delayed effects in adults. This study provided a novel approach for assessing the sublethal effects of pyriproxyfen on C. claveri, contributing valuable information to enhance IPM strategies.

Understanding the sublethal effects of insecticides on non-target insects is essential for integrated pest management (IPM). This study aimed to evaluate the differentially expressed genes (DEGs) in the testes of Ceraeochrysa claveri adults exposed to pyriproxyfen during the larval stage. Larvae (0–12 h) were fed Diatraea saccharalis eggs treated with pyriproxyfen (50 and 100 mg a.i. L−1) for 10 days. After this exposure, the larvae were fed untreated eggs until pupation. The testes from the adults were extracted for RNA extraction, library construction, and sequencing. The reads were de novo assembled, and the genes annotated based on their ORF homology. A total of 46 DEGs were identified for the 50 mg a.i. L−1 vs. control, 47 DEGs for the 100 mg a.i. L−1 vs. control, and 64 DEGs for 50 mg vs. 100 mg a.i. L−1 treatments. To validate the DEGs through RT-qPCR, the genes BPHL, Large2, MLX, and Talin-1 were selected. The results indicate that the exposure of C. claveri larvae to pyriproxyfen could alter the gene expression and lead to delayed effects in adults. This study provided a novel approach for assessing the sublethal effects of pyriproxyfen C. claveri and contributed valuable information to enhance IPM strategies.