SUSCEPTIBILITY AND VULNERABILITY OF THIRD-INSTAR LARVAE OF THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE) TO <i>BACILLUS THURINGIENSIS</i> SUBSP. <i>KURSTAKI</i>
Bibliographic record
Abstract
Abstract A droplet-imbibing assay was used to assess the susceptibility of third-instar larvae of the spruce budworm, Choristoneura fumiferana Clemens, to Foray 48B, a commercial formulation of Bacillus thuringiensis subsp. kurstaki containing 12.7 billion international units (IU) per litre. We observed an LD50 of 1.17 IU/larva for third instars, as compared with 3.96 IU/larva for fifth instars. Comparison with previously published data on susceptibility of later instars revealed that third instars were two-to three-fold more susceptible to Foray 48B than fourth and fifth instars and about eightfold more susceptible than sixth instars. Vulnerability of third instars to simulated aerial spray deposits was investigated by using potted balsam firs, Abies balsamea L. Potted trees were infested in the greenhouse when the buds were starting to swell, using a density of about one newly emerged second-instar larva per bud. When 90% of the larvae had reached the third instar and 52% of the buds were breaking (4 d after infesting), infested twigs were harvested and sprayed with undiluted Foray 48B in a spray chamber. Spray droplets on the buds measured between 25 and 125 μm in diameter, with 80% having a diameter of 80 μm or less. A density of 4.2 ± 1.0 droplets per bud resulted in spruce budworm mortality of 83.4 ± 4.0% and a corresponding reduction in larval density of 86.5 ± 3.9% (means ± SD, n = 6) after 5 d at 25 °C. Results of the spray chamber test suggest that third-instar spruce budworms were able to acquire a lethal dose, despite their concealed feeding habits.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".