First report of Telenomus remus Nixon (Hymenoptera: Scelionidae) on Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in Egypt

Abstract

BackgroundThe polyphagous alien invasive pest, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), invaded Africa and has so far spread across the continent, causing devastating impacts on maize production. In Egypt, the management of the pest by maize growers has been characterized by the application of broad-spectrum synthetic chemical insecticides, a strategy which is associated with various detrimental effects on the environment and human health. To mitigate the overreliance and excessive use of those synthetic chemicals, biological control using egg parasitoids species provides an ecologically friendly and sustainable management strategy. In that regard, this study had the objective of identifying the natural existing egg parasitoids, which could be effectively used in augmentative biocontrol of the pest in Egypt.ResultsFor the first time in Egypt, natural occurrence and parasitism of Telenomus remus Nixon, 1937 (Hymenoptera: Scelionidae) on S. frugiperda egg masses was recorded. Infested maize farms in Qena Governorate, Egypt, were surveyed, and S. frugiperda egg masses were collected and incubated in the laboratory. Emerging parasitoids’ wasps were grouped based on their morphological similarities. Natural parasitism of the egg parasitoids (Telenomus sp.) was computed from the parasitized field collected egg masses. In addition, to confirm the laboratory parasitism and suitability of the parasitoid, Telenomus sp. to develop on S. frugiperda, the parasitoid was reared on S. frugiperda egg masses for three generations under laboratory conditions. Moreover, both morphological and molecular identifications were conducted. The recovered parasitoid samples from the field S. frugiperda egg masses were Telenomus remus (Nixon) (Hymenoptera: Scelionidae). Moreover, the average field parasitism level by T. remus on S. frugiperda was 15.9%, while under laboratory conditions, the parasitism was 63.5%.ConclusionsThe natural occurrence of T. remus in Egypt and its association with S. frugiperda is an important finding upon which augmentative biocontrol strategy can be leveraged on to sustainably manage the pest populations.