Kerry L. Weber
Todd J. Severson
Theresa M. Schreier
Denise A. Mayer
Douglas B. Aloisi
Nathan L. Eckert
James A. Luoma
2015
<p>The study was completed to evaluate the exposure-related effects of a biopesticide for dreissenid mussel (<i>Dreissena polymorpha</i>, zebra mussel and <i>Dreissena rostriformis bugensis</i>, quagga mussel) control on glochidia from unionid mussels endemic to the Great Lakes and Upper Mississippi River Basins. The commercially prepared biopesticide was either a spray-dried powder (SDP) or freeze-dried powder (FDP) formulation of <i>Pseudomonas fluorescens</i>, strain CL145A. Glochidia of the unionid mussel species <i>Lampsilis cardium</i>, <i>Lampsilis siliquoidea</i>,<i>Lampsilis higginsii</i>, <i>Ligumia recta</i>, <i>Obovaria olivaria</i>, and <i>Actinonaias ligamentina</i> were exposed to SDP-formulated <i>P. fluorescens</i> and<i>Lampsilis cardium</i> and <i>Megalonaias nervosa</i> were exposed to FDP-formulated <i>P. fluorescens</i>.</p>
<p>All exposures were static, 24 hours in duration, and included six treatment groups. The treatment groups included (1) an untreated control, (2) a positive control which received a nominal target active ingredient (AI) concentration of 300 milligrams per liter (mg/L) of heat-deactivated test article, and (3) treatments that received nominal target AI concentrations of 50, 100, 200, and 300 mg/L of test article. All treatment concentrations are reported based on active ingredient.</p>
<p>Glochidia viability was reduced in two of the six species exposed to 50 mg/L SDP and in four of the six species exposed to 100 mg/L SDP when compared to untreated control groups at 6, 12, and 24 hours. Regardless of sample time, concentrations of 200 and 300 mg/L of SDP and 300 mg/L of heat-deactivated SDP (positive control) substantially reduced glochidia viability in all species except, <i>L</i>. <i>higginsii</i>. Glochidia viability was only reduced for L. cardium exposed to FDP at concentrations ≥ 200 mg/L. After 24 hours of FDP exposure, differences in glochidia viability were only detected in <i>M</i>. <i>nervosa</i> that were exposed to 300 mg/L of heat-deactivated SDP. However, given the low viability in the control group, the results for <i>M</i>. <i>nervosa</i> should be interpreted with caution.</p>
application/pdf
10.3133/ofr20151094
en
U.S. Geological Survey
Exposure-related effects of formulated <i>Pseudomonas fluorescens</i> strain CL145A to glochidia from seven unionid mussel species
reports