D3063: Using Beauveria bassiana to control corn earworm (Helicoverpa zea) in hemp

Entomopathogenic fungi, such as Beauveria bassiana and Metarhizium anisopliae, have shown
promise in controlling corn earworm(CEW) (Helicoverpa zea) in hemp fields. These fungi are
natural enemies of insects and can infect and kill corn earworm larvae. When applied to hemp
plants, entomopathogenic fungi produce spores that attach to the insect's cuticle. The spores then
germinate and penetrate the insect's body, ultimately causing the insect to die. This process can
take several days when the infected insect becomes less mobile and may stop feeding. As a
result, entomopathogenic fungi can reduce corn earworm damage to hemp plants and improve
crop yields. This research aims to optimize these fungi use and determine the most effective
application methods in hemp fields. Entomopathogenic fungi are considered a low-toxicity
alternative to synthetic pesticides, and a limited number of pesticides are registered in hemp
against CEW. However, the efficacy of entomopathogenic fungi may depend on several factors,
including environmental conditions, application rate, and application timing. Based on the three
years study from our research group on the population dynamics of CEW, the optimized fungi
suspension will be applied to the hemp field at different time points, and data on the mortality
and hemp damage will be collected. On preliminary laboratory assay, some field collected
Beauveria bassiana showed promise to control CEW.