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Table 1 Comparison of critical elements in bitrophic feeding trials of both studies

From: A controversy re-visited: Is the coccinellid Adalia bipunctata adversely affected by Bt toxins?

Critical elements Alvarez-Alfageme et al. [8] Schmidt et al. [1]
Parameter/methods Number of test insects Not clear, probably 34 to 41 30
  Number of replicates Not clear, probably 1 4
  Total number of test insects per treatment N = 34 to 41 N = 120
  Diet treatment Water/sugar solution (2 droplets) with Bt toxin Meal moth eggs treated with Bt toxin in buffer solution
  Diet control Water/sugar solution (no buffer added)
Untreated meal moth eggs
Meal moth eggs treated with empty constructs in buffer solution
Meal moth eggs treated with buffer solution (3 separate control treatments; see below)
  Dose(s) of administered Bt toxins 1 each 3 each (for each Bt-concentration treatment, a separate control was carried out; 3 control treatments)
  Exposure time (per instar) to Bt toxin 4 × 1 day (1 day during each instar followed by recovery periods)
Total development time 12 days (Bt) to 17 days (other treatments)
9 to 10 days continuous (all instars)
Total development time 9 to 10 days
  Exposed life stages Partially, all 4 instars Continuously, all 4 instars
  ELISA with A. bipunctata larvae to verify uptake No No
  Quantification of ingested amount of Bt toxin No No
Results Control mortality (%) Number of control treatments = 1 Number of control treatments = 3 + 3 pBD10 = 6
   L1-P = 15.0% L1-P = 15.8%, 21.7%, 10.8% (15.0%, 13.3%, 10.8%)
L1-A = 16.7%, 21.7%, 14.2% (15.8%, 15.0%, 14.2%)
  Treatment mortality (%) 1 dose of each Bt toxin 3 doses of each Bt toxin
  Cry1Ab 45 5 25 50
  concentration μg/ml μg/ml μg/ml μg/ml
     L1-P 20.6% 26.7% 48.3% 35.8%
     P 3.7% 1.2% 1.6% 0
     L1-A 24.3% 27.5% 49.2% 35.8%
  Cry3Bb 200 5 25 50
  concentration μg/ml μg/ml μg/ml μg/ml
     L1-P 17.1 21.7% 32.5% 30.0%
     P 0 0 1.2% 1.2%
     L1-A 17.1 21.7% 33.5% 30.8%
  1. ELISA, enzyme-linked immunosorbent assay.