Intraguild Interactions of Three Biological Control Agents of the Fall Armyworm Spodoptera frugiperda (JE Smith) in Florida

Abstract

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a maize pest worldwide. Its host range comprises more than 350 reported plant species, and it is the primary insect pest attacking maize in Florida. Global trade has not only assisted but accelerated its invasion into the Eastern Hemisphere. Regular pesticide use promotes resistance in the species; therefore, there is an urgent need for alternative pest management strategies. This study evaluated the interactions of biological control agents within a similar guild. Some of the reported interactions could potentially lead to the integration of these agents within the same niche to increase biological control efficiency against the fall armyworm. We evaluated three biocontrol agents that are natural enemies of Lepidopteran pests, the true bugs Podisus maculiventris and Euthyrhynchus floridanus (Hemiptera: Pentatomidae) and a parasitoid, Cotesia marginiventris (Hymenoptera: Braconidae). Depending on their intraguild interactions, these agents could potentially be useful for biological control of the fall armyworm. The study investigated these three biocontrol agents and concluded that integrating these agents to control the fall armyworm is a possibility; however, only under certain conditions. Investigations were focused on evaluating the predator–parasitoid and devised pairing interactions. Predator response to prey in a choice or no-choice scenario and choices based on olfaction or other bodily cues were studied under experimental laboratory conditions.

Estimating the Cost of Production of Two Pentatomids and One Braconid for the Biocontrol of Spodoptera frugiperda (Lepidoptera: Noctuidae) in Maize Fields in Florida

“…All colonies were initially collected from existing colonies that had been in rotation for at least two years prior. Colonies of the pentatomids P. maculiventris and E. floridanus , the parasitoid C. marginiventris, and the fall armyworm S. frugiperda for this evaluation were reared according to colony establishment protocols described in Perier et al [ 29 ].…”

“…Because the parasitoid prefers maize-plant-feeding larvae, these second instars were fed maize leaf clippings and maize kernels before the introduction of the parasitoid. Parasitism had to be visually confirmed after the introduction and required exact experimental conditions [ 29 ]. Parasitism could take up to 30 min.…”

“…Then, the parasitized larvae were stored in 1 oz. cups and fed the Multiple Species Diet until emergence [ 29 ].…”

“…Natural enemies emerged in many cases as an alternative to the adverse effects of conventional control in our ecosystems due to its increased sustainability [ 25 ]. A practical method for S. frugiperda control in the Americas is biological control agents [ 27 , 28 , 29 ]. These agents have regulated the species for eons and have coevolved with their pest counterparts.…”

“…Another biological control agent, Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae), is a common parasitoid emerging from parasitized S. frugiperda larvae from field collections [ 28 , 32 ]. All three insects were previously evaluated and shown to be capable of simultaneous use, under the correct timing and life stage conditions, for controlling S. frugiperda [ 29 ].…”