Synergistic effects of Bacillus velezensisSDTB038 and phenamacril on Fusarium crown and root rot of tomato

Abstract

Fusarium crown and root rot (FCRR) is a damaging ailment that can affect tomato production. It is caused by Fusarium oxysporum f. sp. radicis‐lycopersici (FORL). The use of biological agents, in conjunction with fungicides, has become a practical strategy for combating fungal diseases in crops. Lipopeptide extracts from a potential biocontrol strain of Bacillus velezensis (SDTB038) exhibited an inhibitory effect on the mycelial growth of FORL; the EC50 value was 59.95 mg/L, and at a concentration of 256 mg/L the inhibition rate reached 97.4%. The SDTB038 strain produces metabolites such as protease and siderophores. Additionally, it is capable of forming a biofilm and swimming. Phenamacril, an antifungal agent, also displayed an inhibitory effect on FORL, demonstrating an EC50 value of 1.074 mg/L. The control effects of the combination of Bacillus velezensis SDTB038 and phenamacril against FORL on tomato plants were also studied in the greenhouse. The combination of phenamacril and 108 CFU/mL SDTB038 fermentation broth exhibited a strong synergistic control effect on FORL, of up to 84.0%. The combination also led to a 35.6% increase in tomato yield compared to the control. These results demonstrate that SDTB038 possesses antifungal activity. Moreover, when combined with phenamacril, it exhibits a strong synergistic effect against FORL. This solution proves to be an effective means of controlling FCRR in tomato plants.

The Combined Effects of Azoxystrobin and the Biosurfactant-Producing Bacillus sp. Kol B3 against the Phytopathogenic Fungus Fusarium sambucinum IM 6525

“…The enhanced antifungal effect of bacteria from the genus Bacillus, when applied in combination with some synthetic pesticides, has been reported before [31][32][33][34][35]. For example, Peng and co-workers [31] studied a possible synergistic effect of B. subtilis NJ-18 with flutolanil and difenoconazole fungicides.…”

“…In another study, Liu and co-workers [33] found that the combined application of the biological agent B. subtilis H158 and synthetic fungicide strobilurin demonstrated a stronger inhibitory effect of rice sheath blight compared to strobilurin alone. Similarly, Chen and co-workers [35] showed that lipopeptide extracts from B. velezensis SDTB038, combined with the fungicide phenamacril, exhibited strong synergistic control against F. oxysporum f. sp. radicis-lycopersici, resulting in an 84% reduction in fungal growth.…”

“…As was previously mentioned, iturin is a biosurfactant exhibiting strong antifungal activity. To the best of our knowledge, there have been no studies of AZ influence on iturin production by Bacillus bacteria, even though there have been several studies on improved bacilli action against phytopathogenic fungi in the presence of different synthetic fungicides, including strobilurins [31][32][33][34][35].…”