Larvicidal activity of different entomopathogenic fungi on Halyomorpha halys (Heteroptera: Pentatomidae) under laboratory conditions

Abstract

Halyomorpha halys, represents a significant threat to a diverse array of agricultural crops. The most prevalent method of control employed against H. halys in integrated fruit production is the use of chemical insecticides. Because of environmental concerns that arise from pesticide use, there is a pressing demand to identify alternative and more sustainable control measures that could serve as a potential substitute or supplement to conventional insecticides. Against this background, entomopathogenic fungi can be seen as a potential management tool worthy of further investigation. In the present study, the effects of egg spray treatments with two Beauveria bassiana-based mycopesticides and conidial suspensions of B. bassiana, B. pseudobassiana, Metarhizium brunneum and M. robertsii isolates were investigated under constant laboratory conditions (25 °C, 65% RH, 16L:8D). Egg hatching rate and nymphal mortality were recorded. Treatment of eggs with the selected fungi resulted in reduced nymph survival compared to a water-treated control. The fungal treatments did not significantly affect hatching success but increased mortality of first instar nymphs, with average mortality rates between 70% and 100% during development from egg to imago. The efficacy of the investigated fungi was demonstrated to be high under specific laboratory conditions, indicating a potential suitability of these fungi as biocontrol agents.

Keywords

• biocontrol
• brown marmorated stink bug
• bioassay
• mycopesticides
• beauveria
• metarhizium