Growers also have no varietal resistance to help combat BPB, and that’s what Zhou and others hope to find with large-scale screening for variety resistance. They also are looking for biocontrol agents to help suppress BPB.

Zhou screened more than 60 varieties and elite lines from southern states in field trials at the Beaumont Research Center and at Eagle Lake.

“We found no varieties or lines completely immune to the disease,” Zhou reported. “Most of the varieties and lines, including CL111, CL 142-AR, CL 181-AR, CL 261, Cocodrie, Jazzman and Templeton were susceptible or highly susceptible. Jupiter, Neptune, Presidio, Rondo and the hybrids (XL 723, CLX 729, and CLX 745) were among the varieties showing partial resistance.”

He said the two bacterial biocontrol strains (Bacillus subtillis) most effective in suppressing BPB among more than 70 bacterial strains tested in the greenhouse were evaluated in artificially-inoculated field trials.

“Spraying rice panicles at flowering with either biocontrol strain reduced BPB severity by 41 percent to 50 percent and increased yield by 11 percent to 17 percent,” Zhou said. “Treatment with the antibiotic oxalinic acid was the most effective, reducing BPB by 86 percent and increasing yield by 21 percent. Integrated use of the bacterial biocontrol agents with partially resistant varieties may provide practical solutions to minimize the damage caused by BPB.”

  • Zhou recommended rice farmers follow some basic cultural practices to manage the disease.
  • Use partially resistant varieties.
  • Do not plant infected seeds.
  • Plant early to avoid late season high temperatures.
  • And avoid excess nitrogen rates.