Differences in parasitic ability of Beauveria bassiana (Moniliales: Moniliaceae) in relation to Pantana phyllostachysae (Lepidoptera: Lymantridae) when feeding on different Phyllostachys pubescens (Poales: Poaceae) leaves

Differences in composition of on-year, off-year and new leaves in Phyllostachys pubescens (moso bamboo) forests will affect the resistance of Pantana phyllostachysae larvae and the parasitic ability of Beauveria bassiana. Pantana phyllostachysae fed on mixed leaves of on-year, off-year and new bamboo leaves. The activities of acetylcholine esterase (AChE) and glutathione S-transferase (GSTs) in P. phyllostachysae larvae fed on mixed leaves were significantly higher, greatly reducing the pathogenicity of B. bassiana to P. phyllostachysae larvae compared with the treatments of off-year and new bamboo leaves. The phenoloxidase (PO) activity in P. phyllostachysae larvae feeding on mixed leaves varied within three days after parasitization by B. bassiana, which indicated higher and less changeable PO activity compared with treatments of off-year and new bamboo leaves. Inclusion of new leaves differed greatly due to its growth, in which, both AChE and GSTs activities were higher than the off-year leaf treatment, leading to a lower pathogenicity of B. bassiana to P. phyllostachysae larvae feeding on new leaves compared with off-year leaves. On the contrary, the pathogenicity of B. bassiana to P. phyllostachysae larvae feeding on on-year leaves was lower than other treatments. AChE and GSTs activities in P. phyllostachysae larvae were lower and PO activity was less changeable, which might be related to the disadvantage of the larval surface structure to B. bassiana infection in the on-year leaf treatment.