Take-off time of the first generation of the overwintering small brown planthopper, Laodelphax striatellus in the temperate zone in East Asia.

Sachiyo Sanada-Morimura,Yijun Zhou,Akira Otuka,Masaya Matsumura,Tomoki Etoh,Yeqin Zhu,Gufeng Zhang,Raul Narciso Carvalho Guedes

doi:10.1371/journal.pone.0120271

Abstract

Overseas migration of the small brown planthopper, Laodelphax striatellus (Fallén), occurs during the winter wheat harvest season in East Asia. Knowing the take-off time of emigrating L. striatellus is crucial for predicting such migrations with a simulation technique because winds, carriers of migratory insects, change continuously. Several methods were used in China and Japan from late May to early June 2012 and again in 2013 to identify the precise timing of take-off. These methods included: a tow net trap mounted to a pole at 10 m above the ground, a helicopter-towed net trap, and a canopy trap (which also had video monitoring) set over wheat plants. Laodelphax striatellus emigrated from wheat fields mainly in the early evening, before dusk. The insects also emigrated during the daytime but rarely emigrated at dawn, showing a pattern that is unlike the bimodal emigration at dusk and dawn of two other rice planthoppers, the brown planthopper, Nilaparvata lugens (Stål), and the white-backed planthopper, Sogatella furcifera (Horváth). There was no significant difference in the temporal pattern of take-off behavior between females and males of Japanese L. striatellus populations.

Highlights

Long-distance movement is one of the primary reasons for the evolutionary success of insects throughout the world [1]
The daily number of L. striatellus caught in the net trap at Tongzhou in 2012 was low, not more than 13 insects, until June 7
No L. striatellus were caught by the light traps, except for two specimens caught at Site 1 (S1) in 2013. These results indicate that most L. striatellus in these two seasons did not fly during the night between 2100 to 0430 h Japanese Standard Time (JST)

Summary

Introduction

Long-distance movement is one of the primary reasons for the evolutionary success of insects throughout the world [1]. Insect species migrate long distances utilizing favorable upper winds, and occasionally even fly over the ocean into another continent, i.e. the painted lady butterfly, Vanessa cardui (Linnaeus) [2, 3]. Long-distance migration is problematic especially when some viruliferous insect pests that damage agricultural crops in one area can migrate into new unaffected areas and transmit pathogenic viruses to crops, causing serious. Take-Off Time of Laodelphax striatellus in East Asia collection and analysis, decision to publish, or preparation of the manuscript

Methods

Results

Conclusion