Fig. 3: Activity of spraying Bt on comb or pressing Bt into the foundation against the GWM.

a The loss rates of combs sprayed with 5, 15, 45, and 135 µg/mL Bt solution and invaded for 4 weeks by 2nd instar GWM larvae. b Comb sprayed with crude BiotGm insecticidal crystal protein and kept at room temperature for 0 (D0), 1 (D7), 2 (D14), 3 (D21) and 4 (D28) weeks followed by invasion by 2nd instar GWM larvae for 1, 2 and 6 months. Combs sprayed with 50 mM Na₂CO₃ solution as SC and without any treatment were used as CK. Comb loss rate data were replaced by arcsine square-root (sqrt) transformation before performing a two-sided unpaired Student’s t-test to analyse the differences between groups. c The effect of insecticidal activity of five Bt products after continuous heating at 25, 70, 75, 80, and 85 °C for 6 h. Boxplots indicate median (centerline), mean ± SE (box), and the maximum and minimum values (upper and lower whiskers). Significance was determined by a two-sided chi-square test. Data are presented as the mean ± SE of three independent biological replicates. The same letters above the bars indicate no significant differences between groups (P > 0.05). d The survival of 2nd instar GWM larvae exposed to the comb foundation containing Bt (4000 μg/g) for 12 days. Comb foundations without any treatment were used as CK. Data were based on four independent biological replicates. Kaplan–Meier survival analysis and two-sided log-rank tests were used to identify differences in survival between groups. All ***P-value ≤ 0.001 for CK vs G033A, CK vs G033A-1, CK vs KN11, CK vs KN11-1, and CK vs BiotGm, and exact P-values is shown in Supplementary Table 3. Source data are provided as a Source Data file.