Comparing the efficacy of various aerial spraying scenarios using Bacillus thuringiensis to protect trees from spruce budworm defoliation

2019 ◽  
Vol 432 ◽  
pp. 1013-1021 ◽  
Author(s):  
Alvaro Fuentealba ◽  
Alain Dupont ◽  
Christian Hébert ◽  
Richard Berthiaume ◽  
Roberto Quezada-García ◽  
...  
Keyword(s):  
Bacillus Thuringiensis ◽  
Spruce Budworm ◽  
Aerial Spraying

AERIAL SPRAYING OF A BACILLUS THURINGIENSIS — CHITINASE FORMULATION FOR CONTROL OF THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)

1973 ◽  
Vol 105 (12) ◽  
pp. 1535-1544 ◽  
Author(s):  
W. A. Smirnoff ◽  
J. J. Fettes ◽  
R. Desaulniers
Keyword(s):  
Bacillus Thuringiensis ◽  
Larval Mortality ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Insect Development ◽  
Check Plot ◽  
The Third ◽  
Spray Deposit ◽  
Aerial Spraying

AbstractA 10,000 acre stand of mature balsam fir, in Temiscouata County, Quebec, which had a spruce budworm population of about 21 larvae/18 in. branch-tip was sprayed with a Bacillus thuringiensis + chitinase formulation. Aerial spraying was carried out by three TBM aircraft between 4 and 7 June 1972, when insect development was at the peak of the third instar. Where the quantity of B. thuringiensis colonies per square centimeter was higher than 77 and spray deposit higher than 0.4 gal/acre (U.S.), larval mortality was between 84% and 93% compared with between 39% and 53% in the check plot. Foliage protection was 47%. The results indicate the possibilities of using B. thuringiensis + chitinase to control spruce budworm infestations.

LONG TERM STUDY OF THE EFFECTIVENESS OF AERIAL APPLICATION OF BACILLUS THURINGIENSIS – ACEPHATE COMBINATIONS AGAINST THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1977 ◽  
Vol 109 (9) ◽  
pp. 1239-1248 ◽  
Author(s):  
O. N. Morris
Keyword(s):  
Bacillus Thuringiensis ◽  
Choristoneura Fumiferana ◽  
Larval Mortality ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
White Spruce ◽  
Balsam Fir ◽  
Population Densities ◽  
Long Term Study

AbstractBacillus thuringiensis (Dipel® 36B) mixed with a sublethal concentration of acephate (Orthene®) (O, S-dimethyl acetylphosphoramidothioate), an organophosphorous insecticide, was applied at 2.35–14 l./ha to white spruce (Picea glauca) and balsam fir (Abies balsamea) trees infested with spruce budworm, Choristoneura fumiferana (Clem.). The treatment rate was 20 Billion International Units of B. thuringiensis (B.t.) activity with or without 42 g of active ingredient of acephate/ha.The ground deposit of the standard Dipel wettable powder formulation was 12% of emitted volume compared with 21–32% for the Dipel 36B flowable. The viability of B.t. spores was drastically reduced after 1 day of weathering but a high level of biological activity by the spore–crystal complex persisted for up to 20 days post-spray due probably to crystal activity.The addition of about 10% of the recommended operational rate of acephate to the B.t. suspension increased larval mortality by 34% when applied at 4.7 l./ha. Reductions in budworm populations were 97–99% in B.t. + acephate plots and 86–90% in B.t. alone plots.Plots with moderate budworm densities of up to 27 larvae/100 buds on white spruce and 36/100 on balsam fir were satisfactorily protected from excessive defoliation in the year of spray by B.t. with or without acephate. Plots with higher population densities were not satisfactorily protected based on the branch sample examination but aerial color photographs indicated good protection to the top third of the trees. Population declines were greater and defoliation and oviposition were lower in the treated plots than in the untreated checks 1 year later without further treatment. Two years later the larval population densities in all plots were low but the density was twice as high in the untreated check as in the treated plots, indicating long term suppression by the treatments. Defoliation was negligible in all plots.The treatments had no deleterious effect on spruce budworm parasitism. The data indicate that the integrated approach using Bacillus thuringiensis – chemical pesticide combinations is a viable alternative to the use of chemical pesticides alone in spruce budworm control. Large scale testing is now warranted.

EFFECT OF TEMPERATURE ON THE PATHOGENESIS OF BACILLUS THURINGIENSIS BERLINER IN LARVAE OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA CLEM. (LEPIDOPTERA: TORTRICIDAE)

1994 ◽  
Vol 126 (4) ◽  
pp. 1061-1065 ◽  
Author(s):  
Kees van Frankenhuyzen
Keyword(s):  
Bacillus Thuringiensis ◽  
Bacterial Growth ◽  
Choristoneura Fumiferana ◽  
Larval Mortality ◽  
Lethal Dose ◽  
Spruce Budworm ◽  
Effect Of Temperature ◽  
Vegetative Cells ◽  
Time Required ◽  
Peak Abundance

AbstractThe relationship between temperature and pathogenesis of Bacillus thuringiensis Berliner var. kurstaki in infected larvae of the eastern spruce budworm, Choristoneura fumiferana Clem., was investigated to determine if more rapid death of larvae with an increase in temperature could be accounted for by enhanced bacterial growth. Cumulative mortality of larvae force-fed with a lethal dose of HD-1-S-1980 peaked within 2 days at 25 °C, 3 days at 19 °C, 7 days at 16 °C, and 21 days at 13 °C. The progress of bacterial growth in the larvae was followed from spore germination to cell lysis, and was completed within 4 days at 25 °C, 6 days at 22 °C, 12 days at 19 °C, 14 days at 16 °C, and > 28 days at 13 °C. Peak abundance of vegetative cells in the larvae was observed after 1 day at 25 °C, 2 days at 22 °C, 3 days at 19 °C, 7 days at 16 °C, and 21 days at 13 °C, and thus coincided almost exactly with the time required for maximum larval mortality. This correlation suggests that the observed effect of temperature on progression of larval mortality was due to its effect on the proliferation of vegetative cells in the infected larvae, and that bacterial septicemia makes an important contribution to death.

scholarly journals Aerial spraying of bacterial insecticides to control spruce budworm defoliation leads to reduced carbon losses

Ecosphere ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Zelin Liu ◽  
Changhui Peng ◽  
Louis De Grandpré ◽  
Jean‐Noël Candau ◽  
Timothy Work ◽  
...  
Keyword(s):  
Spruce Budworm ◽  
Aerial Spraying ◽  
Carbon Losses

RELATIVE POTENCIES OF 50 ISOLATES OF BACILLUS THURINGIENSIS FOR LARVAE OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1983 ◽  
Vol 115 (7) ◽  
pp. 815-822 ◽  
Author(s):  
O. N. Morris ◽  
A. Moore
Keyword(s):  
Bacillus Thuringiensis ◽  
Choristoneura Fumiferana ◽  
Larval Growth ◽  
Spruce Budworm ◽  
Relative Potencies

AbstractFifty Bacillus thuringiensis (B.t.) isolates representing K-1, galleriae, K-73, thuringiensis, aizawai, dendrolimus, tolworthi, kenyae, darmstadiensis, alesti, and entomocidus crystal antigen types were bioassayed against fifth-instar spruce budworm, Choristoneura fumiferana (Clem.), larvae. In addition, larvae reared on diet with and without aureomycin were tested for their susceptibility to B.t. The data indicated no significant differences in susceptibility to B.t. among insects reared on aureomycin or on aureomycin-free diet, but differences were evident in larval growth and mortality among untreated controls. None of the 50 isolates bioassayed was any more toxic to the budworm than is the strain used at present in commercial preparations of B. thuringiensis.

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