Fig. 4

a Nematode production (IJs ml⁻¹) in larvae of Rhynchophorus ferrugineus treated with Bt-k (70 µg g⁻¹), Beauveria bassiana (1 × 10⁷ conidia ml⁻¹) and Heterorhabditis bacteriophora (300 IJs ml⁻¹) applied alone or in combination. Treatments followed by the same letter within each treatment are not significantly different; HSD test P ≤ 0.05 (Bt-k: Bacillus thuringiensis var. kurstaki, Bb: Beauveria bassiana, EPN: Heterorhabditis bacteriophora). b Nematode production (IJs ml⁻¹) in adults of Rhynchophorus ferrugineus treated with Bt-k (70 µg g⁻¹), Beauveria bassiana (1 × 10⁷ conidia ml⁻¹) and Heterorhabditis bacteriophora (300 IJs ml⁻¹) applied alone or in combination. Treatments followed by the same letter within each treatment are not significantly different; HSD test P ≤ 0.05 (Bt-k: Bacillus thuringiensis var. kurstaki, Bb: Beauveria bassiana, EPN: Heterorhabditis bacteriophora)