MYCOLab Ai Logo - gold and army green

Biocontrol of Cercospora leaf spot in sugar beet by a novel Bacillus velezensis KT27 strain: Enhanced antifungal activity and growth promotion in laboratory and field conditions

Summary

This research demonstrates that a beneficial bacteria called Bacillus velezensis KT27 can effectively control a common fungal disease in sugar beet crops. The bacteria fights the disease by producing natural antifungal compounds and can be further enhanced by exposure to inactivated fungal pathogens. Field trials showed the bacterial treatment provided disease protection almost as good as chemical fungicides while also promoting plant growth and increasing sugar beet yield by up to 15%.

Background

Cercospora leaf spot (CLS), caused by Cercospora beticola, is a severe disease affecting sugar beet cultivation with yield losses up to 40%. Increasing fungicide resistance and environmental concerns necessitate sustainable alternatives. Bacillus velezensis strains have demonstrated potential as biocontrol agents through production of antimicrobial metabolites and plant growth-promoting traits.

Objective

This study investigated the antagonistic activity of a newly isolated Bacillus velezensis KT27 strain against Cercospora beticola and evaluated its potential as a biocontrol agent for Cercospora leaf spot in sugar beet under laboratory and field conditions.

Results

B. velezensis KT27 inhibited C. beticola growth by 60.2% in vitro, with enhanced activity when induced by inactivated R. cerealis (33.5% increase). The strain solubilized phosphorus (53.3 mg/L) and potassium (45.8 mg/L) effectively. Field trials showed B. velezensis KT27 + R. cerealis achieved 96.4% disease suppression at first application and 50% overall, with root yield increase of 15.2% compared to untreated control.

Conclusion

Bacillus velezensis KT27 represents a promising and environmentally sustainable biocontrol agent against Cercospora leaf spot in sugar beet, achieving disease suppression only 9.1% lower than chemical fungicides while promoting plant growth through nutrient solubilization. The strain’s efficacy can be significantly enhanced through induction by inactivated fungal pathogens, particularly R. cerealis.
  • Published in:PLoS One,
  • Study Type:Field Trial with Laboratory Validation,
  • Source: 10.1371/journal.pone.0323889, PMID: 40445985
Scroll to Top