scholarly journals Persistence of insecticidal activity of novel bio-encapsulated formulations of Bacillus thuringiensis var. kurstaki against Choristoneura rosaceana [Lepidoptera: Tortricidae]

2005 ◽  
Vol 82 (2) ◽  
pp. 73-82 ◽  
Author(s):  
J.-C. Côté ◽  
C. Vincent ◽  
K.-H. Son ◽  
S. H. Bok
Keyword(s):  
Bacillus Thuringiensis ◽  
Insecticidal Activity ◽  
Meteorological Factors ◽  
Larval Mortality ◽  
Apple Orchard ◽  
Choristoneura Rosaceana ◽  
Obliquebanded Leafroller ◽  
Higher Doses

DiPelTM, a registered Bacillus thuringiensis var. kurstaki (Btk)-based formulation, and experimental bio-encapsulated Btk formulations were sprayed in an apple orchard. Their persistence was assessed in the laboratory against obliquebanded leafroller (Choristoneura rosaceana) larvae for three consecutive years. In 1995, DiPel and the bio-encapsulated formulation caused significantly higher larval mortality than the control at least 1 day, and up to 27 days after treatments, respectively. In 1996, although 6.4 mm of rain fell during the day of treatments, DiPel and the bio-encapsulated formulation caused respectively 21 and 33% larval mortality immediately after treatments. DiPel caused significantly higher mortality than the control for up to 3 days while the bio-encapsulated formulation caused significantly higher mortality for up to 14 days. In 1997, two Btk strains (HD-1 and BMP123) were sprayed at different concentrations in a.i. (3 and 8%) and doses (30 and 240 g 15 L-1 applied). Higher concentrations of a.i. in the Btk formulations and higher doses sprayed increased the persistence of the insecticidal activity. Among the meteorological factors that were measured (i.e. precipitations, temperature and solar radiations), precipitations reduced the persistence of the insecticidal activity. Solar radiations may have modulated the persistence of the formulations.

scholarly journals Apple, Control of the Obliquebanded Leafroller with Bacillus Thuringiensis Products in Summer, 1993

1995 ◽  
Vol 20 (1) ◽  
pp. 5-5
Author(s):  
J. F. Brunner
Keyword(s):  
Bacillus Thuringiensis ◽  
Apple Orchard ◽  
Treatment Evaluation ◽  
Post Treatment ◽  
Summer Generation ◽  
Obliquebanded Leafroller

Abstract Different B. thuringiensis products were evaluated for their ability to control OBLR larvae of the summer generation. The test was conducted in an apple orchard near Milton-Freewater, OR. Trees were 2-yr-old ‘Delicious’ on dwarfing roots. The orchard was ditch irrigated. Treatments were applied on 6 and 17 Jul to five-tree plots replicated five times using a RCBD. All treatments were applied with a handgun sprayer at 300 psi to the point of drip, simulating a dilute spray of approximately 400 gpa. The post-treatment evaluation was made on 29 Jul. Each tree was examined and the number of live leafroller larvae recorded.

Nucleopolyhedrovirus infection in obliquebanded leafroller (Lepidoptera: Tortricidae)

2002 ◽  
Vol 134 (3) ◽  
pp. 303-309 ◽  
Author(s):  
I. Pronier ◽  
J. Paré ◽  
J-C Wissocq ◽  
C. Vincent
Keyword(s):  
Fat Body ◽  
Larval Mortality ◽  
Adult Emergence ◽  
Control Group ◽  
Choristoneura Rosaceana ◽  
Obliquebanded Leafroller ◽  
Naturally Occurring ◽  
The Family ◽  
Microscopic Studies ◽  
Occlusion Bodies

AbstractA virus isolated from obliquebanded leafroller, Choristoneura rosaceana (Harris), larvae collected in an apple, Malus domestica Borkh. (Rosaceae), orchard of Saint-Joseph-du-Lac (Quebec, Canada) was studied. Microscopic studies revealed that it was a uninucleocapsid nucleopolyhedrovirus from the family Baculoviridae. Larval mortality was approximately 75% (0% mortality in control group) in larvae infected as third instars immersed in a suspension of 1.7 × 108 occlusion bodies/mL. The average time for larval mortality was 23 ± 3 d after treatment. The majority (95.5%) of infected larvae died as fifth or sixth instars. Infection was observed primarily in fat body cells, and occasionally in the tracheal matrix and epidermis. Mean larval development time of infected larvae surviving to pupae was 20 ± 3 d, significantly greater than the 18 ± 3 d observed in control larvae. Adult emergence was significantly lower in pupae of treated larvae (73.6%) than in the control group (93.5%). Our work constitutes the first baseline study of naturally occurring virus of the obliquebanded leafroller.

scholarly journals Apple, Control of the Obliquebanded Leafroller with Bacillus Thuringiensis and Cryolite in Summer, 1994

1995 ◽  
Vol 20 (1) ◽  
pp. 6-6
Author(s):  
J. F. Brunner ◽  
M. D. Doerr ◽  
L. O. Smith
Keyword(s):  
Bacillus Thuringiensis ◽  
Apple Orchard ◽  
Treatment Evaluation ◽  
Post Treatment ◽  
Summer Generation ◽  
Obliquebanded Leafroller

Abstract Different B. thuringiensis products and Kryocide (cryolite) were evaluated for their ability to control OBLR larvae of the summer generation. The test was conducted in an apple orchard near Milton-Freewater, OR. The trees were 3-yr-old ‘Delicious’ on dwarfing roots. Treatments were applied to four-tree plots replicated five times using a RCB design. All treatments were applied on 23, 30 Jun and 11 Jul with a handgun sprayer at 300 psi to the point of drip, simulating a dilute spray of approximately 400 gpa. The post-treatment evaluation was made on 27 Jul. The number of live OBLR larvae on all four trees of a treatment replication was counted.

scholarly journals Apple, Control of the Obliquebanded Leafroller with Bacillus Thuringiensis and Conventional Products in Spring, 1993

1995 ◽  
Vol 20 (1) ◽  
pp. 5-5
Author(s):  
J. F. Brunner
Keyword(s):  
Bacillus Thuringiensis ◽  
Plant Development ◽  
Apple Orchard ◽  
Treatment Evaluation ◽  
Post Treatment ◽  
Development Stages ◽  
Obliquebanded Leafroller

Abstract Different B. thuringiensis products were evaluated for their ability to control OBLR larvae of the overwintering generation. The test was conducted in an apple orchard near Milton-Freewater, OR. Trees were 4-yr-old ‘Fuji’ on dwarfing roots. Treatments were applied to four-tree plots replicated five times in a RCBD. All treatments were applied with a handgun sprayer at 300 psi to the point of drip, simulating a dilute spray of approximately 400 gpa. Application dates and plant development stages are shown in the table. The post-treatment evaluation was made on 20 May. Each tree was examined and the no. of live leafroller larvae recorded.

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.

EFFECT OF TEMPERATURE ON TOXICITY OF BACILLUS THURINGIENSIS TO THE OBLIQUEBANDED LEAFROLLER (LEPIDOPTERA: TORTRICIDAE)

1995 ◽  
Vol 127 (2) ◽  
pp. 271-273 ◽  
Author(s):  
S.Y. Li ◽  
S.M. Fitzpatrick ◽  
M.B. Isman
Keyword(s):  
British Columbia ◽  
Bacillus Thuringiensis ◽  
First Generation ◽  
Effect Of Temperature ◽  
Choristoneura Rosaceana ◽  
Harvesting Time ◽  
Obliquebanded Leafroller ◽  
Major Pest ◽  
Fraser Valley ◽  
Heavy Infestation

In recent years, the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), has become a major pest of raspberries in the Fraser Valley, British Columbia (Anonymous 1994). Overwintering C. rosaceana larvae begin feeding on raspberry leaf buds in early April. Heavy infestation causes serious damage to raspberry plants. Larvae of the first generation hatch in late June to early July, and feed on growth terminals and berries. The occurrence of this generation usually coincides with berry harvesting time. Because the larvae are shaken from the plants by the harvesting machine, C. rosaceana can be a major contaminant of machine-harvested berries.

scholarly journals Apple, Obliquebanded Leafroller Control with Bacillus Thuringiensis Plus Adjuvants in Summer, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 9-9
Author(s):  
J. F. Brunner ◽  
M. D. Doerr ◽  
L. O. Smith
Keyword(s):  
Bacillus Thuringiensis ◽  
Apple Orchard ◽  
Treatment Evaluation ◽  
Post Treatment ◽  
Summer Generation ◽  
Obliquebanded Leafroller ◽  
Dipel 2X

Abstract Dipel 2X, alone and in combination with two spreader adjuvants, Latron B-1956, and Sylgard 309, and the Able and Biobit were evaluated for their ability to control OBLR larvae of the summer generation. The test was conducted in an apple orchard at Mattawa, WA. The trees were 3-yr-old Delicious on dwarfing roots. Treatments were applied to 8-tree plots replicated five times in a randomized complete block. All treatments were applied with a handgun sprayer at 300 psi to the point of drip simulating a dilute spray of approximately 400 gal/acre. The post-treatment evaluation was made on 26 Jul. The total number of live OBLR larvae found in a 10-min search on all 8 trees of a treatment replication was counted.

scholarly journals Efficacy of Ricinus communis L., Cassia occidentalis L. and Bacillus thuringiensis against Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

2021 ◽  
Vol 3 (3) ◽  
pp. 46-53
Author(s):  
Waleed Elamin Elhaj ◽  
Abdelgadir Ahmed Osman ◽  
Loai Mohamed Elamin Elawad
Keyword(s):  
Bacillus Thuringiensis ◽  
Insecticidal Activity ◽  
Ricinus Communis ◽  
Larval Instar ◽  
Larval Mortality ◽  
Cassia Occidentalis ◽  
Potentiation Effect ◽  
Ricinus Communis L ◽  
And Control ◽  
Lepidoptera Noctuidae

Helicoverpaarmigera is one of the most destructive pests of field crops worldwide. The Study was designed to investigate through laboratory screening the insecticidal activity of Ricinus communis, Cassia occidentalis and Bacillus thuringiensis var. Kurstaki (Btk) and their combinations against 2nd larval instar of H. armigera. Five concentrations (4%, 6%, 8%, 10% and 12%) of each plant extract and (0.62, 1.25, 2.5, 5, and 10 mg/ml) of Bt were used in this experiment. Mortality (%) was recorded after 24,48,72 and 96 hrs post treatment. The results showed that R. communis, C. occidentalis and Btkhave insecticidal activity against 2nd instar larvae of H. armigera. The highest concentration (12%) caused 80% and 70% larval mortality after 96 hrs for R. communis and C. occidental respectively. The statistical analysis revealed that there is a significant differences between all treatments and control. Additionally, all combinations (plant/plant or plant/Bt) increased the mortality %. The results also clearly demonstrate that the R. communis are significantly more toxic than C. occidental where the LC50 values were 6.4 % for R. communis and 8.1% for C. occidental. On the other hand LC50 value for Bt was 0.41 mg/ml. The binary mixture of R. communis and C. occidental have a potentiation effect after 48 hrs. Regarding the mixture of Bt and plant extracts the results revealed that R. communis and Bt mixture induced a potentiation effect whereas C. occidental and Bt mixture induced a an additive effects.

THE EFFECTS OF APPLICATION RATE AND SPRAY VOLUME ON EFFICACY OF TWO FORMULATIONS OF BACILLUS THURINGIENSIS BERLINER VAR. KURSTAKI AGAINST CHORISTONEURA ROSACEANA (HARRIS) (LEPIDOPTERA: TORTRICIDAE) ON RASPBERRIES

1996 ◽  
Vol 128 (4) ◽  
pp. 605-612 ◽  
Author(s):  
S.Y. Li ◽  
S.M. Fitzpatrick
Keyword(s):  
Bacillus Thuringiensis ◽  
Residual Activity ◽  
Life Time ◽  
Field Studies ◽  
Application Rate ◽  
Choristoneura Rosaceana ◽  
Original Activity ◽  
Obliquebanded Leafroller ◽  
Application Rates ◽  
Spray Volume

AbstractThe relative toxicities of two formulations (Dipel WP and Foray 48B) of Bacillus thuringiensis Berliner var. kurstaki to the obliquebanded leafroller, Choristoneura rosaceana (Harris), were determined in the laboratory. The effects of application rate (BIU per hectare) and spray volume (litres per hectare) on the efficacy of Dipel WP and Foray 48B against C. rosaceana were determined in raspberry fields. Mortality of C. rosaceana increased with application rate, and decreased with an increase in spray volume. Bacillus thuringiensis exhibited significantly longer residual activity al higher application rates and at lower spray volumes. The half-life (time at which 50% of original activity remains) of B. thuringiensis ranged from 2.45 to 6.68 days, depending upon application rate and spray volume. Laboratory and field studies indicate that Dipel WP and Foray 48B are highly and equally effective in killing larvae of C. rosaceana.

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