Species composition and seasonal dynamics of aphid parasitoids and hyperparasitoids in wheat fields in northern China

Qian Wang,Juli Pujade-Villar,Michael Traugott,Lei Xu,Zhi-Wen Yao,Yue-Kun Wu,Fan Yang,Vladimir Žikić,Nicolas Desneux,Jesús Selfa,Yan-Hui Lu,Yu-Yuan Guo,Željko Tomanović,Mar Ferrer-Suay

doi:10.1038/s41598-017-14441-6

Abstract

Parasitoids are important natural enemies of aphids in wheat fields of northern China, and interest in them has increased in recent years. However, little is known regarding parasitoids of wheat aphids, which has hindered the study and understanding of aphid-parasitoid interactions. In the present study, three primary parasitoids and 15 hyperparasitoids were collected in wheat fields during a 2-year survey in northern China (2014, 2015) and a 2-year investigation at Langfang, Hebei Province (2015, 2016). Among them, Aphidius uzbekistanicus Luzhetski was found most frequently among the primary parasitoids, while Pachyneuron aphidis (Bouché) dominated the hyperparasitoid community. Investigation of the dynamics of wheat aphids and parasitoids revealed that the primary parasitoids appeared early in the growing period and that the hyperparasitoids appeared later. Analysis of the seasonal dynamics revealed that growth of the parasitoid population followed that of the aphid population and that the parasitism rates were highest in the late growing period.

Highlights

Parasitoids are important natural enemies of aphids in wheat fields of northern China, and interest in them has increased in recent years
In 2015, 1,276 primary parasitoid individuals belonging to three species and 2,048 hyperparasitoid individuals belonging to 14 species emerged from the mummies collected within 30 wheat fields
The primary parasitoids recorded by these studies consisted of six species: Aphidius avenae Haliday, A. gifuensis, A. ervi, Ephedrus persicae Froggatt, E. plagiator (Nees), and Praon sp.[25]; one additional species, Lipolexis gracilis (Förster), was present the following year by the same authors as before[1]

Summary

Introduction

Parasitoids are important natural enemies of aphids in wheat fields of northern China, and interest in them has increased in recent years. Most of the literature on wheat aphid parasitoids in China is focused on primary parasitoids, species of Aphidiinae[1,2,26,27,28,29,30,31,32]. Comprehensive information about the aphid-parasitoid species is missing and the dominant species of aphid hosts, primary parasitoids, and hyperparasitoids at different growing periods is still unknown. We investigated (1) the parasitoid species composition in 18 wheat fields in 2014 and 30 fields in 2015 in northern China (Figs 1 and 2) the population dynamics of wheat aphids and their parasitoids in Langfang, Hebei Province from 2015–2016.

Results

Conclusion