Lethal and sublethal effects of Bacillus thuringiensis var. kurstaki on aquatic insects in laboratory bioassays and outdoor stream channels

1992 ◽  
Vol 49 (2) ◽  
Author(s):  
DavidP. Kreutzweiser ◽  
StephenB. Holmes ◽  
ScottS. Capell ◽  
DavidC. Eichenberg
Keyword(s):  
Bacillus Thuringiensis ◽  
Aquatic Insects ◽  
Sublethal Effects ◽  
Stream Channels ◽  
Laboratory Bioassays

HIGH-DOSAGE TREATMENT OF A QUEBEC STREAM WITH BACILLUS THURINGIENSIS SEROVAR. ISRAELENSIS: EFFICACY AGAINST BLACK FLY LARVAE (DIPTERA: SIMULIIDAE) AND IMPACT ON NON-TARGET INSECTS

1985 ◽  
Vol 117 (12) ◽  
pp. 1523-1534 ◽  
Author(s):  
C. Back ◽  
J. Boisvert ◽  
J.O. Lacoursière ◽  
G. Charpentier
Keyword(s):  
Bacillus Thuringiensis ◽  
Aquatic Insects ◽  
Artificial Substrates ◽  
High Dose ◽  
Artificial Turf ◽  
Insect Larvae ◽  
Commercial Formulation ◽  
Lake Outlet ◽  
Pre Treatment ◽  
Drifting Larvae

AbstractA typical lake outlet of the Canadian Shield was treated for 15 min with a high dose (5.28 g/L s−1 of discharge) of Teknar®, a commercial formulation of Bacillus thuringiensis serovar. israelensis. Efficacy on Simuliidae larvae and impact on non-target aquatic insects of this stream were monitored using drift nets, counting plates, and artificial turf substrates along a 1000-m section downstream of the site of application. Compared with a 4-day pre-treatment average for 12-h sampling periods, drift of Simuliidae increased from 64 to 92 ×, with shorter peaks of 133–184 ×, 2–6 h after treatment. There was no evident drift increase in larvae of Ephemeroptera, Plecoptera, Trichoptera, Chironomidae, or dipterous pupae, but larvae of Blephariceridae (Diptera) were severely affected as their drift was increased by up to 50 × and remained high for 3 days. After 30 h the mortality of Simuliidae on counting plates ranged from 95 to 82% in the first 300 m, with detachment rates of 78.5–46.5%. Densities of non-target insect larvae were not reduced on the artificial substrates, except for 2 genera of Chironomidae (Eukiefferella and Polypedilum) which were reduced 26 to 39% of their original density. Drifting larvae of 1 chironomid genus (Phaenopsectra) also showed symptoms of toxemia by B.t.i. The main impact of the treatment was thus seen in 2 Nematocera families (Chironomidae and Blephariceridae) which were mainly exposed to B.t.i. sedimented on the bottom of the stream or attached to periphyton growing on rocks.

Sublethal effects of Bacillus thuringiensis on the spruce budworm, Choristoneura fumiferana

1997 ◽  
Vol 83 (3) ◽  
pp. 253-262 ◽  
Author(s):  
Anita Pedersen ◽  
John Dedes ◽  
Debbie Gauthier ◽  
Kees Frankenhuyzen
Keyword(s):  
Bacillus Thuringiensis ◽  
Sublethal Effects ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm

scholarly journals The effects of Kingbo biopesticide on Tetranychus urticae Koch female adults

2013 ◽  
Vol 28 (3) ◽  
pp. 195-202 ◽  
Author(s):  
Irena Medjo ◽  
Dejan Marcic
Keyword(s):  
Tetranychus Urticae ◽  
Spider Mite ◽  
Sublethal Effects ◽  
Recovery Potential ◽  
Petri Dishes ◽  
Set Up ◽  
Two Spotted Spider Mite ◽  
Tetranychus Urticae Koch ◽  
Laboratory Bioassays ◽  
Concentration Series

Toxic and sublethal effects of the biopesticide Kingbo (oxymatrine 0.2% + psoralen 0.4%) on female adults of two-spotted spider mite (Tetranychus urticae Koch) were investigated in two laboratory bioassays. The assays were set up in four replicates on bean leaf discs (30 mm in diameter) placed on moistened cotton wads in Petri dishes. Preovipositional females were then released on them and treated directly with the biopesticide at a concentration series using a Potter device (2 ml liquid, 100 kPa air pressure, 2.7 ? 0.2 mg/cm2 aqueous deposit). Each replicate included 4-7 Petri dishes containing a total of 20-35 females. In the first assay, females were exposed to continuous acaricidal activity on treated discs over a period of 96 h; in the second assay, they were exposed for 24 h and then transferred to untreated discs and kept there for the next 72 h. Kingbo toxicity to females, expressed as LC50, was significantly higher in the first bioassay (14.83 ?l/l) than in the second one (26.39 ?l/l). Total gross fecundity of females in the first assay was reduced by 37-95% and net fecundity by 48-97%, depending on concentration; in the second assay, the respective fecundity reductions were 15-87% and 23-91%. We found that a 24 h exposure to the biopesticide Kingbo was sufficient for sustaining significant toxic and sublethal effects. Further research should provide additional data on the recovery potential of T. urticae populations.

scholarly journals Apple, Obliquebanded Leafroller Control with Spinosad, Bacillus Thuringiensis, Abamectin and Chlorpyrifos in Spring, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 8-8 ◽  
Author(s):  
J. F. Brunner ◽  
M. D. Doerr ◽  
L. O. Smith
Keyword(s):  
Bacillus Thuringiensis ◽  
Plant Development ◽  
Growth Regulator ◽  
Sublethal Effects ◽  
Adult Emergence ◽  
Development Stage ◽  
Insect Growth Regulator ◽  
Apple Orchard ◽  
Obliquebanded Leafroller ◽  
Dipel 2X

Abstract Spinosad, 80% (formulation NAF-127, DowElanco); Bacillus thuringiensis (Bt) (Dipel 2X, Abbott Laboratories), abamectin Agri-Mek 0.15 EC (Merck & Co., Inc.) and chlorpyrifos (Lorsban 4E, DowElanco) were evaluated for their ability to control OBLR larvae of the overwintering generation. The test was conducted in an apple orchard in Mattawa, WA. The trees were 3-yr-old Delicious on dwarfing roots. Treatments were applied to 12-tree plots replicated 5 times in a randomized complete block. All treatments were applied with a handgun sprayer at 300 psi to the point of drip. Application dates were 5 Apr (pink) and 9 May (petal fall). Approximate application timings with regard to plant development stage are shown in the table. The post-treatment evaluation was made on 24 May by a count of the total number of live OBLR larvae on all trees of a treatment replication. Live larvae were collected to observe sublethal effects. Surviving larvae were reared on artificial leafroller diet in 3.25 oz portion cups until death or adult emergence. Any deformities possibly resulting from exposure to an insect growth regulator were recorded. Weather was good, calm winds and moderate temperatures, at the time of applications.

TOXICITY OF BACILLUS THURINGIENSIS VAR. KURSTAKI TO AQUATIC INSECTS

1985 ◽  
Vol 117 (7) ◽  
pp. 829-837 ◽  
Author(s):  
D.C. Eidt
Keyword(s):  
Bacillus Thuringiensis ◽  
Aquatic Insects ◽  
Water Bodies ◽  
Continuous Exposure ◽  
Concentration Effects ◽  
Buffer Zones ◽  
Worst Case ◽  
Simulium Vittatum ◽  
Spray Rate

AbstractRepresentative aquatic insects, larvae of Simuliidae, Chironomidae, Trichoptera, Megaloptera, and nymphs of Ephemeroptera and Plecoptera, were tested for susceptibility to continuous exposure to Bacillus thuringiensis Berliner var. kurstaki at 4.3, 43, and 430 IU/mL. Only Simulium vittatum was affected, and at the highest concentration. Effects on other organisms, particularly Prosimulium fuscum/mixtum, were suggested. The lowest of the concentrations tested was twice the worst-case transitory concentration peaks expected in water from aerial forest spraying at 30 BIU/ha. Spray buffer zones around water bodies are unnecessary at this spray rate.

Concentration–Mortality Response of Mexican Populations Fall Armyworm (Lepidoptera: Noctuidae) to Commercial Formulations of Bacillus Thuringiensis

2021 ◽  
Vol 56 (1) ◽  
pp. 70-83
Author(s):  
María del Carmen Lara-Becerra ◽  
Manuel Alejandro Tejeda-Reyes ◽  
Ángel Lagunes-Tejeda ◽  
Gonzalo Silva-Aguayo ◽  
J. Concepción Rodríguez-Maciel
Keyword(s):  
Bacillus Thuringiensis ◽  
Spodoptera Frugiperda ◽  
Zea Mays L ◽  
Fall Armyworm ◽  
Mortality Response ◽  
Important Pest ◽  
Median Lethal Concentrations ◽  
Lepidoptera Noctuidae ◽  
Laboratory Bioassays ◽  
Mexican Populations

Abstract The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is the most economically important pest of maize (Zea mays L.) grown in Mexico. In order to identify biologically based management tactics for this pest, we determined the concentration–mortality response of 16 S. frugiperda populations collected in Mexico to two commercial formulations of Bacillus thuringiensis Berliner (Bt) (XenTari® [Bt subsp. aizawai] and DiPel® [Bt subsp. kurstaki]; Valent de México SA De CV, Jalisco, México). Laboratory bioassays established median lethal concentrations (LC50s) for each Bt formulation × population combination. We also determined mean larval weight 7 d after exposure and the number of larvae that reached the third instar of development. The populations were susceptible to both Bt formulations but they were, overall, more susceptible to Bt subsp. aizawai (XenTari) than to Bt subsp. kurstaki (DiPel). These results can serve as a reference to detect changes in S. frugiperda response to these Bt commercial products over time.

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