First report of Telenomus remus parasitizing Spodoptera frugiperda and its field parasitism in southern China

Yong-Lin Liao,Ke-Wei Chen,De-Sen Wang,Hua-Yan Chen,Miao-Feng Xu,Wei Lin,Bin Yang

doi:10.3897/jhr.73.39136

Abstract

The fall armyworm, Spodoptera frugiperda, is a lepidopteran pest that feeds on many economically important cereal crops such as corn, rice, sorghum, and sugarcane. Native to the Americas, it has become a serious invasive pest in Africa and Asia. Recently, this pest was found in China and has spread quickly across the country. As S. frugiperda will most likely become a major pest in China, Integrated Pest Management strategies, including biological control methods, should be developed to manage its populations. Here, we report the detection of Telenomus remus parasitizing S. frugiperda eggs in cornfields in southern China based on morphological and molecular evidence. Our preliminary surveys indicated that the parasitism rates of T. remus on S. frugiperda could reach 30% and 50% for egg masses and per egg mass, respectively. Further application of T. remus against S. frugiperda in biological control programs are discussed.

Highlights

The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), which originates from tropical and subtropical areas of North, Central, and South America, has become an invasive pest of cereals in Africa, India, Myanmar, Thailand, etc, where it has caused serious damage (Kenis et al 2019)
The cytochrome oxidase subunit 1 (COI) sequences were identical among females and males sampled from the three collecting sites, and over 99% of the pairs of bases were identical to a series of sequences labeled as T. remus available from the Barcoding of Life Data system and the GenBank database
Phylogenetic analysis based on COI sequences generated from this study and those used by Kenis et al (2019) showed that the six specimens collected from the three sites of southern China were grouped well within the clade of T. remus specimens collected from Asia, Africa, and the Americas (Figure 2)

Summary

Introduction

The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), which originates from tropical and subtropical areas of North, Central, and South America, has become an invasive pest of cereals in Africa, India, Myanmar, Thailand, etc, where it has caused serious damage (Kenis et al 2019). Just for corn, rice, sorghum and sugarcane, this pest could cause up to 13 billion USD per annum in crop losses in Africa (Day et al 2017). Sugarcane, and rice are widely grew in southern China, S. frugiperda will most likely establish as a major pest in this region (Wang et al 2019). Chemical control is still the main strategy against this pest in China, some biological control experiments using predators (Picromerus lewisi Scott (Hemiptera: Pentatomidae)) have been conducted in the laboratory (Tang et al 2019). In the long run, more biological control strategies should be adopted to against S. frugiperda under the perspectives of Integrated Pest Management (IPM)

Methods

Results

Conclusion