Pollen tube integrity is critical for thermotolerance in tomato and is enhanced by loss of SlRALF1.

Loss of the pollen-expressed RALF signaling peptide enhances thermotolerance by maintaining pollen tube integrity under heat stress in tomato.

• Why it matters: Understanding how heat stress affects pollen function is crucial for improving reproductive success and crop resilience in changing climates.
• What they did: The study examined four pollen-expressed RALF peptides and found that disrupting one improves thermotolerance; heat stress was shown to antagonize RALF signaling involved in pectin distribution in pollen tubes.
• The result: These findings suggest that modifying RALF signaling pathways can promote thermotolerant pollen tube growth, providing a molecular basis for breeding heat-resilient tomato cultivars.