Efficaciousness of field-collected and commercial entomopathogenic strains of Beauveria bassiana on mortality of kudzu bug, Megacopta cribraria

When kudzu bug, Megacopta cribraria, was identified in the United States in 2009 as an invasive species, populations began to establish, increase, and spread throughout the southeastern region at intense rates. The kudzu bug is known for its’ tendencies to invade urban structures, causing unpleasant scenes for homeowners, and reduce crop yield, such as soybean. Kudzu bug caused about $1,000,000 in soybean yield loss and treatment in Tennessee in 2019. Although initial invasion was rapid throughout the southeastern United States, spatial modeling has shown populations of kudzu bug are declining and reducing risk of crop damage to growers. These local and regional declines in populations appear to be influenced by at least two natural enemies, a naturally-occurring entomopathogenic fungus, Beauveria bassiana, and an accidentally introduced egg parasitoid, Ooencyrtus nezarae. O. nezarae causes 52% mortality in kudzu bug eggs and B. bassiana causes about 90% and 33% mortality in second-generation immature kudzu bugs and adult kudzu bugs, respectively. Localized population declines reduced the number of adult kudzu bugs surviving and overwintering by about 97%. The establishment and success of these natural enemies to cause mortality of kudzu bug will play an important role in driving population dynamics to maintain population declines in the southeastern United States. The purpose of this presentation is to provide information on the impact of field- collected and commercial entomopathogenic strains of B. bassiana on kudzu bug mortality over time in east Tennessee, with implications for the United States.