Friendly Soil Bacterium Bacillus velezensis JS6-1 Protects Muskmelons from Devastating Postharvest Rot

Friendly Microbe Fights Off Deadly Melon Rot: The Promise of Bacillus velezensis JS6-1

A research team from the Xinjiang Academy of Agricultural Sciences has discovered that the soil bacterium Bacillus velezensis JS6-1 can effectively combat Fusarium solani, the fungus responsible for severe postharvest rot in muskmelons. The study, published in Current Microbiology (2025), highlights the strain’s dual role in both directly inhibiting fungal growth and boosting the fruit’s natural defense system.

The scientists found that B. velezensis JS6-1 secretes volatile organic compounds (VOCs) and bioactive molecules such as lipopeptides (iturin, fengycin, surfactin) that damage the pathogen’s mycelia. Proteomic analysis identified 12 antibacterial proteins contributing to this antifungal activity.

In greenhouse trials, applying the bacterium’s fermentation broth significantly reduced decay rates in infected muskmelons. Moreover, enzyme assays revealed heightened activity of superoxide dismutase (SOD), peroxidase (POD), and phenylalanine ammonia lyase (PAL)—key defense enzymes that help the fruit resist further infection.

The strain’s antimicrobial properties remained stable under varying pH, temperature, and UV exposure, underscoring its resilience and suitability for agricultural application.

According to lead author Yafang He, B. velezensis JS6-1 could serve as a promising biological control agent, offering farmers an eco-friendly solution to replace chemical fungicides that harm the environment and reduce fruit quality.

This study lays the groundwork for developing sustainable postharvest treatments that harness beneficial microbes to protect fruit, ensuring safer produce and longer shelf life.

Reference

He, Y., Wei, J., Chen, F., Wang, N., Han, Y., Wu, Z., Wang, X., Zhan, F., Shi, Y., Yang, R., & Bao, H. (2025). Biocontrol Effects and Potential Defence Mechanism of Bacillus velezensis JS6-1 Against Fusarium solani-Induced Postharvest Rots in Muskmelon. Current Microbiology, 82(12), 553. https://doi.org/10.1007/s00284-025-04522-5