New Discovery of a Beneficial Bacteria That Protects Tomatoes from Wilt Disease

Greg Howard
23rd May, 2024

Image Source: Natural Science News, 2024

Key Findings

Researchers from Northeast Agricultural University discovered a beneficial bacteria strain, NEAU-CP5, from tomato seeds
NEAU-CP5, identified as Bacillus velezensis, produces antibacterial substances that fight the harmful Ralstonia solanacearum
Applying NEAU-CP5 to tomato plants reduced bacterial wilt by over 68% and boosted the plants' natural defenses

Bacterial wilt of tomato, caused by Ralstonia solanacearum, is a severe soilborne disease that significantly impacts tomato yield. A recent study by Northeast Agricultural University has identified an endophytic strain, NEAU-CP5, with potent antagonistic activity against R. solanacearum, offering a promising biocontrol solution^[1]. Ralstonia solanacearum is notorious for causing bacterial wilt in various crops, including tomatoes, bananas, and potatoes^[2]. Traditional control methods, such as crop rotation and sanitation practices, have had limited success due to the pathogen's persistence in soil^[2]. Recent advances have focused on biological control agents (BCAs) such as bacteria and fungi, which have shown potential in managing bacterial wilt^[3]. In the current study, the researchers isolated NEAU-CP5 from tomato seeds and identified it as Bacillus velezensis through 16S rRNA gene and whole genome sequence analysis. B. velezensis is known for its ability to produce a range of antibacterial metabolites, which were confirmed in NEAU-CP5. These metabolites include cyclo (leucylprolyl), cyclo (phenylalanyl-prolyl), and several others, which contribute to its strong antibacterial activity. The study also identified fourteen gene clusters in the NEAU-CP5 genome associated with antibacterial properties, reinforcing its potential as an effective biocontrol agent. This genetic insight aligns with previous genomic studies on R. solanacearum, which have emphasized the importance of understanding pathogen and biocontrol agent genomes to develop effective control strategies^[2]. In pot experiments, the application of NEAU-CP5 at a concentration of 108 CFU/mL on tomato plants significantly reduced the incidence of bacterial wilt by 68.36 ± 1.67%. This reduction is substantial, considering the challenges in controlling soilborne pathogens. Additionally, NEAU-CP5 enhanced the activity of defense-related enzymes in tomato plants, such as catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). These enzymes play crucial roles in plant defense mechanisms, indicating that NEAU-CP5 not only directly antagonizes the pathogen but also boosts the plant's innate defenses. The study is significant as it is the first to report the effective control of tomato bacterial wilt using B. velezensis, highlighting NEAU-CP5's potential as a biocontrol agent. This finding builds on previous research that has explored various BCAs and their mechanisms, emphasizing the importance of integrated pest management (IPM) in controlling bacterial wilt diseases^[3]. In summary, the isolation and characterization of NEAU-CP5 by Northeast Agricultural University provide a promising biocontrol strategy against Ralstonia solanacearum in tomatoes. By leveraging the strain's antibacterial properties and its ability to enhance plant defense mechanisms, this study offers a new avenue for managing bacterial wilt, building on the foundation of earlier research on pathogen control and biocontrol agents^[2]^[3]^[4].

Agriculture Biochem Plant Science

References

Main Study

1) Isolation and identification of NEAU-CP5: a seed-endophytic strain of B. velezensis that controls tomato bacterial wilt.

Published 20th May, 2024

https://doi.org/10.1016/j.micpath.2024.106707

Related Studies

2) Ralstonia solanacearum, a widespread bacterial plant pathogen in the post-genomic era.

https://doi.org/10.1111/mpp.12038

3) Recent trends in control methods for bacterial wilt diseases caused by Ralstonia solanacearum.

https://doi.org/10.1264/jsme2.ME14144

4) Bacterial Wilt in China: History, Current Status, and Future Perspectives.

https://doi.org/10.3389/fpls.2017.01549