# Reduction in Gonad Development and Sperm Motility in Male Brown Planthopper Nilaparvata lugens via RNAi-Mediated Knockdown of tramtrack

## TL;DR

Scientists used RNA interference to show that a gene called tramtrack is crucial for male reproduction in a rice pest, suggesting a new way to control the pest.

## Contribution

This study identifies tramtrack as a key gene in male reproductive development in Nilaparvata lugens, offering a novel RNAi target for pest control.

## Key findings

- RNAi knockdown of ttk in male brown planthoppers reduced gene expression by up to 80%.
- Knockdown caused 8–89% volume reductions in male reproductive organs and 60–85% reduction in sperm motility.
- Fertilization success dropped by 73% in eggs from treated males, with embryonic development arrested.

## Abstract

The brown planthopper Nilaparvata lugens, a major rice pest, threatens global food security through rapid reproduction. This study investigates the role of the tramtrack (ttk) gene in male reproductive development and spermatogenesis using RNA interference (RNAi). Gene expression analysis revealed higher ttk levels in testes. RNAi-mediated knockdown of ttk in fourth-instar male nymphs reduced its expression by up to 80%, leading to severely impaired gonad development. Testes, vas deferens, and accessory glands in treated males exhibited 8–89% volume reductions compared to controls, accompanied by a 51–69% decline in sperm count and 60–85% reduction in sperm motility. Consequently, eggs fertilized by treated males showed a 73% decrease in hatching rates, with arrested embryonic development. These findings demonstrate ttk’s critical role in spermatogenesis and gonad maturation in N. lugens, highlighting its potential as an RNAi target for sustainable pest control strategies.