Biological characteristics of two pathogens causing brown blotch in Agaricus Bisporus and the toxin identification of Cedecea neteri

Abstract

Brown blotch disease in Agaricus bisporus reduces its commercial value, resulting in significant economic losses. The pathogens of brown blotch disease are diverse. Current research on the biological characteristics and toxins has been limited to Pseudomonas tolaasii but lacks understanding of other pathogens. Understanding the biological characteristics of the pathogens and identifying their toxins are essential prerequisites for disease prevention and control. This study isolated two pathogens from brown discoloration in A. bisporus in Guangxi, China, and identified them as Pseudomonas tolaasii and Cedecea neteri. C. neteri exhibited stronger resistance to sodium dodecyl sulfate (SDS) and H2O2 and a broader pH adaptation range than P. tolaasii. P. tolaasii showed higher swimming motility than C. neteri. C. neteri produces two toxins identified as phenylacetic acid and p-hydroxybenzoic acid, causing browning symptoms in A. bisporus at 20 μg and 10 μg, respectively. The present study compared various biological characteristics between P. tolaasii and C. neteri. The toxins produced by C. neteri were extracted and identified, and their toxicity to A. bisporus was evaluated, which is the first report on C. neteri toxins. These discoveries have enhanced our understanding of the biological characteristics and biotoxins of C. neteri. The research findings offer new insights for developing novel disease prevention and control strategies.