Biological Agents in The Control of Sclerotinia in Soybean Cultivation (Glycine max L.)

Objective: The objective of this study is to evaluate the effectiveness of biological agents (Trichoderma and Bacillus) in controlling the fungus Sclerotinia sclerotiorum (white mold) in soybean cultivation, aiming to verify their influence on reducing the sclerotia bank in the soil and the economic viability of these practices as a sustainable alternative to chemical fungicides.

 

Theoretical Framework: The theoretical framework highlights the economic importance of soybeans and the impact of diseases, focusing on white mold caused by Sclerotinia sclerotiorum. It addresses biological control as a sustainable alternative, emphasizing the use of Trichoderma and Bacillus. It presents the concept of integrated disease management and the complexity of control due to the resistance of sclerotia. These foundations support the proposed investigation.

 

Method: A quantitative, experimental, and applied approach was used. The experiment was conducted in a controlled environment (greenhouse/laboratory) at UNOCHAPECÓ from February to May 2024. Three treatments were applied (control, Trichoderma, and Bacillus), with 10 replicates each, totaling 100 sclerotia per treatment. Pathogen development was monitored at 7, 14, and 21 days. A cost-benefit analysis was also carried out based on the product cost and effectiveness in disease control. Statistical analysis used ANOVA and Tukey’s test (p≤0.05).

 

Results and Discussion: Results showed that Bacillus was the most effective agent, with the lowest growth rates of S. sclerotiorum. Trichoderma, despite higher colonization, was less efficient in controlling the pathogen. The control group showed continuous infection progression, confirming the effectiveness of biological treatments. The discussion contextualizes the findings with literature, indicating Bacillus as promising in integrated management, while Trichoderma may still be useful in combined strategies.

 

Research Implications: This research has practical implications for sustainable soybean management, offering alternatives to the excessive use of chemical fungicides. Theoretically, it contributes to advancing knowledge on biological control and emphasizes the importance of integrating different strategies. Fields such as sustainable agriculture, biological input production, and rural extension may benefit from these findings.

 

Originality/Value: This study is original for systematically comparing the effectiveness of two biological agents in white mold control under controlled conditions, using robust statistical and economic analysis. It contributes to the literature by providing practical data for farmers and researchers interested in effective and economically viable biological management.