Use of a Colonization‐Deficient Strain of Escherichia coli in Strain Combinations for Enhanced Biocontrol of Cucumber Seedling Diseases

Seed treatments containing combinations of Escherichia coli S17R1 and Burkholderia cepacia Bc-B provided significantly greater (P ≤ 0.05) suppression of cucumber seedling pathogens in a field soil naturally infested with Pythium and Fusarium spp. than seeds treated individually with strains Bc-B, S17R1, or Enterobacter cloacae 501R3. Although strain S17R1 had no effect on disease severity when applied alone and did not colonize cucumber rhizosphere, it enhanced the biocontrol effectiveness of strain Bc-B.