01974nas a2200229 4500008004100000245013100041210006900172300001200241490000800253520122500261653002301486653001701509653002501526653002601551653002801577653001701605100001901622700001801641700001901659700001801678856004801696 2013 eng d00aMode of Action of Pseudomonas fluorescens Strain CL145A, A Lethal Control Agent of Dreissenid Mussels (Bivalvia: Dreissenidae)0 aMode of Action of Pseudomonas fluorescens Strain CL145A A Lethal a115-1210 v1133 a

Pseudomonas fluorescens strain CL145A (Pf-CL145A) has demonstrated promise as an efficacious and selective agent for the control of macrofouling Dreissena spp. mussels. Herein, we report trials to investigate the mode of action of this biocontrol agent against Dreissena polymorpha, the zebra mussel. Exposure to dead Pf-CL145A cells achieved the same temporal pattern and percentage mussel mortality as did live cells, thereby excluding infection as the possible lethal mode of action. Histological analysis revealed pathologies consistent with the cause of death being intoxicating natural products associated with Pf-CL145A cells. Irrespective of whether the mussels were exposed to live or dead Pf-CL145A cells, examination of tissues from histological sections revealed that: (1) at the end of the 24-h treatment period there was massive hemocyte infiltration into the lumina of both the digestive gland and stomach; and (2) mussel deaths occurred following lysis and necrosis of the digestive gland and sloughing of stomach epithelium. These trials provide strong evidence that the lethal mode of action of Pf-CL145A is intoxication.

10aBiological control10aBiopesticide10aDreissena polymorpha10aHemocyte infiltration10aPseudomonas fluorescens10aZebra mussel1 aMolloy, D., P.1 aMayer, D., A.1 aGiamberini, L.1 aGaylo, M., J. uhttp://dx.doi.org/10.1016/j.jip.2012.12.013