Complementary effect of Phloxine B on the insecticidal efficacy of Isaria fumosorosea SFP-198 wettable powder against greenhouse whitefly, Trialeurodes vaporariorum West

Abstract

Background: Insecticidal activities of five photoactive dyes against greenhouse whitefly (GWF), Trialeurodes vaporariorum West., in tomatoes were investigated to improve the control efficacy of an entomopathogenic fungal product, Isaria fumosorosea SFP-198 wettable powder (WP). Azorubine, Eosin B, Erythrosine, Brilliant Green and Phloxine B were used in this work, accompanying pyriproxyfen emulsifiable concentrate (EC) as a commercial standard for comparison.

Results: Phloxine B had the highest control efficacy in glasshouse conditions. The most suitable dose of Phloxine B was determined as 0.005 g L(-1) , given the dosage-dependent control efficacy and phytotoxicity of the dye, and its influence on the germination of SFP-198 conidia. In field conditions, SFP-198 WP + Phloxine B (2 + 0.005 g L(-1) ; tank mix) showed 89.1 and 95.3% control efficacy 7 and 14 days post-application, which was significantly higher than the efficacy of SFP-198 WP alone (43.5 and 64.0%), Phloxine B (47.5 and 30.7%) or pyriproxyfen EC (67.7 and 80.2%).

Conclusion: Phloxine B cooperates with SFP-198 WP complementarily, possibly in the order of killing action (early: Phloxine B; late: SFP-198 WP). The dye can be incorporated into SFP-198 WP to improve its efficacy and applied to other Hypocrelean entomopathogenic fungal products.