ARS | Publication request: Compatibility of Coniothyrium minitans with Compound Fertilizer in Suppressionof Sclerotinia sclerotiorum

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 24, 2011
Publication Date: December 15, 2011
Citation: Yang, L., Li, G., Zhang, J., Jiang, D., Chen, W. 2011. Compatibility of Coniothyrium minitans with Compound Fertilizer in Suppressionof Sclerotinia sclerotiorum. Biological Control. 59:221-227.

Interpretive Summary: Sclerotinia stem rot is a serious disease of many economically important crops including canola wherever the crop is grown. Management options for this disease are very limited because there is no acceptable resistance in canola and fungicides are not cost effective. Biological control with the biocontrol agent Coniothyrium minitans is very promising. However, application of the biocontrol agent is labor intensive. The research was carried out to see if the application of the biocontrol agent can be combined with fertilizer application, which will save application cost. Results showed that simultaneous application of C. minitans and a compound fertilizer at various concentrations significantly reduced the number of apothecia produced by sclerotia of S. sclerotiorum in both pot and field plot experiments. It demonstrated that C. minitans is compatible with the compound fertilizer when applied at planting of canola. Application of C. minitans together with the compound fertilizer would be advantageous in saving labor cost, thus increasing production efficiency.

Technical Abstract: Coniothyrium minitans is a mycoparasite and a promising biocontrol agent of Sclerotinia sclerotiorum, the causal of Sclerotinia stem rot of oilseed rape. In order to assess whether soil application of C. minitans can be combined with fertilizer application during cultivation of oilseed rape, a study was conducted to determine the compatibility of C. minitans with commercial N-P-K compound fertilizer. Results showed that the compound fertilizer at concentrations of 0.1% to 10% inhibited conidial germination and mycelia growth of C. minitans in a dosage-response manner in vitro. Simultaneous application of C. minitans and the compound fertilizer at various concentrations significantly (P < 0.05) reduced the number of apothecia produced by sclerotia of S. sclerotiorum in both pot and field plot experiments. No negative effects of the compound fertilizer on the ability of C. minitans to infect sclerotia of S. sclerotiorum in vitro or to suppress carpogenic germination of sclerotia of S. sclerotiorum were observed. It is demonstrated that C. minitans is compatible with the compound fertilizer when applied at planting of oilseed rape. Application of C. minitans together with the compound fertilizer would be advantageous in saving labor cost, thus increasing production efficiency of oilseed rape.