PCR assays for specific and sensitive detection of Pseudomonas tolaasii,the cause of brown blotch disease of mushrooms

AIMS: The present study describes PCR assays to detect specifically Pseudomonas tolaasii from various samples. METHODS AND RESULTS: Two sets of PCR primers were developed to amplify genes required for tolaasin production. Only a PCR product of 449 bp or 249 bp was produced in PCR reactions with the Pt-1A/Pt-1D1 or Pt-PM/Pt-QM primer sets, respectively, and DNA and cells of Ps. tolaasii. Nested and immunocapture-nested PCR could detect to 3 cells of Ps. tolaasii and amplify the Ps. tolaasii-specific DNA from a sample containing 10 000 times more other bacterial cells than Ps. tolaasii, respectively. CONCLUSIONS: The PCR assays are simple, rapid and reliable methods for detection and identification of Ps. tolaasii. SIGNIFICANCE AND IMPACT OF THE STUDY: The protocols can effectively distinguish Ps. tolaasii from other bacteria and detect Ps. tolaasii from various samples for studying ecology of the bacterium and preventing the use of contaminated water or spawn or medium in mushroom cultivation.