Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 6/30/2013
Publication Date: 7/5/2013
Publication URL: http://www.apsnet.org/searchcenter/Pages/meetingresults.aspx
Citation: Zhou, X., Mcclung, A.M. 2013. Efficacy of bacillus biocontrol agents for management of sheath blight and narrow brown leaf spot in organic rice. Phytopathology. 103(S2):168.
Technical Abstract: Organic rice production has significantly increased in the U. S. over the last decade. Growers lack effective tools to manage sheath blight, caused by Rhizoctonia solani, and narrow brown leaf spot (NBLS), caused by Cercospora janseana, two major diseases affecting organic rice production. An experiment was conducted in a field under organic management in Texas in 2010 and 2011 to evaluate the efficacy of seven Bacillus biocontrol agents for management of sheath blight and NBLS. Plots were inoculated with R. solani at panicle differentiation. NBLS developed from natural inoculum. When applied at the boot stage, Serenade Max (B. subtilis strain QST713, 14.6% a. i.) and Serenade ASO (B. subtilis strain QST713, 1.34% a.i.) were effective in reducing sheath blight severity in 2011. Serenade Max also reduced NBLS severity in both years. Strain MBI600 (B. subtilis) reduced severity of both sheath blight and NBLS. The other four Bacillus biocontrol agents, including Ballad Plus (B. pumilus), did not effectively reduce both diseases and increase yield. Only Serenade Max consistently increased yield by more than 15% over 2 years. Serenade Max can be used as an effective tool to reduce the damage caused by sheath blight and NBLS in organic rice. Serenade Max is a commercially available biopesticide certified for organic production of rice and other crops.