Drought stress enhances plastid-mediated RNA interference for efficient the willow leaf beetle management

Area of Science:

• Plant biotechnology
• Entomology
• Molecular biology

Background:

• Plastid-mediated RNA interference (RNAi) offers effective pest control by expressing double-stranded RNAs (dsRNAs) targeting essential pest genes.
• Plants often face combined biotic and abiotic stresses, but the impact of abiotic stress on plastid-derived dsRNA accumulation and efficacy is unknown.

Purpose of the Study:

• To investigate the effect of drought stress on dsRNA accumulation in transplastomic poplar plants.
• To evaluate the impact of drought stress on the efficacy of plastid-mediated RNAi against the willow leaf beetle (Plagiodera versicolora).

Main Methods:

• Generating transplastomic poplar plants expressing dsRNA targeting the willow leaf beetle.
• Applying drought stress to these plants under controlled conditions.
• Quantifying dsRNA levels and assessing insect mortality and plant defense compound levels.

Main Results:

• Drought stress did not significantly alter dsRNA content in transplastomic poplar plants.
• Willow leaf beetle larvae exposed to drought-stressed plants exhibited higher mortality rates.
• Water deficit correlated with increased levels of jasmonic acid and cysteine proteinase inhibitor in plants.

Conclusions:

• Plastid-derived dsRNA accumulation is robust under drought stress.
• Drought stress can indirectly enhance RNAi-based pest control efficacy through plant defense mechanisms.
• Understanding these interactions is crucial for optimizing pest management strategies in challenging environmental conditions.