Prospects for classical biological control ofSpodoptera frugiperda(Lepidoptera: Noctuidae) in invaded areas using parasitoids from the Americas

Abstract

Fall armyworm, Spodoptera frugiperda (J.E. Smith) is a polyphagous agricultural pest threatening food security worldwide. This American species recently invaded most of Africa, many Asian countries, and Oceania, where it mainly damages maize. Classical biological control (CBC) through the introduction of natural enemies from its area of origin is considered as a potential management approach. The paper reviews the prospects and constraints of a CBC programme against S. frugiperda using larval parasitoids, which are considered the most suitable natural enemies for introduction against this pest. The most important larval parasitoids in its native range are presented and discussed for their suitability as CBC agents, based the following criteria: their frequency of occurrence and parasitism levels, specificity, climatic suitability and absence of closely related species parasitizing S. frugiperda in the area of introduction. The ichneumonid Eiphosoma laphygmae Costa-Lima (Hymenoptera: Icheumonidae) is considered as a potential candidate for introduction because of its specificity and its importance as a parasitoid of the pest in most of its native range. The most frequent and important parasitoid of S. frugiperda in the Americas, the braconid Chelonus insularis Cresson (Hymenoptera: Braconidae), would most probably contribute to the control of S. frugiperda if released in invaded areas. However, it is oligophagous and would most certainly parasitize nontarget species. Before introducing C. insularis, or any other parasitoid species, the potential nontarget effects will have to be assessed and the risks will have to be weighed against the benefits of improving the natural control of this important pest.

Association of a Global Invasive Pest Spodoptera frugiperda (Lepidoptera: Noctuidae) with Local Parasitoids: Prospects for a New Approach in Selecting Biological Control Agents

“…There are also reports on additional examples, such as the association between the pomegranate whitefly Siphoninus phillyreae (Hemiptera: Aleyrodidae) and local parasitoid Encarsia inaron (Hymenoptera: Aphelenidae) in Egypt [ 90 ], which was successfully controlled with a maximum parasitism rate of 93% with regular release and 36% without release [ 91 ]. Contrary to Kenis’s proposed [ 13 ], our study argues that a new association between T. remus and S. frugiperda is a strong candidate for biological control agents in invaded areas. Hence, classical biological control should not be used in a country with abundant T. remus , and available data already suggest the ability of T. remus to attack and suppress the population of S. frugiperda .…”

“…Chelonus insularis (Hymenoptera: Ichneumonidae) is identified as the primary parasitoid of S. frugiperda in most investigations conducted in North, Central, and South America. However, Eiphosoma laphygmae (Hymenoptera: Icheumonidae) is more recommended as a prospective candidate for introduction because of its specificity and significance as a parasitoid of the pest across most of its natural habitat [ 13 ]. These two parasitoids were not discovered during our research.…”

“…Hokkanen and Pimental [ 18 ] also said that the original host of the most effective new association biocontrol agents is closely connected to the new host of the agent introduced. Moreover, Kenis [ 13 ] also stated that several of the primary parasitoids of S. frugiperda within the invaded range are members of the same genera that could be prospective introduction candidates. The original and subsequent hosts have typically belonged to the same genus.…”

“…A strategy to control S. frugiperda can be created using natural enemies such as parasitoids [ 13 ] to enhance the currently used control strategies, including the use of genetically modified varieties and the overuse of pesticides [ 14 ]. Generally, classical biological control (CBC) involves searching for natural enemies in the pest’s native area, known as the old association [ 15 ], a particularly effective method for managing invasive insects that spread widely and infiltrate various habitats.…”

Hymenopteran parasitoid complex and fall armyworm: a case study in eastern India

“…However, little damage to reproductive tissues may have a greater impact on yield than the foliar damage in the early-whorl growth stages. The crop can compensate for the damage at early stages 34 .…”