&lt;b&gt;Distance from the edge of forest fragments influence the abundance of aphidophagous hoverflies (Diptera: Syrphidae) in wheat fields

Orcial Ceolin Bortolotto,Thiago Augusto Campos,Adriano Thibes Hoshino,Ayres De Oliveira Menezes Junior

doi:10.4025/actasciagron.v38i2.27711

<b>Distance from the edge of forest fragments influence the abundance of aphidophagous hoverflies (Diptera: Syrphidae) in wheat fields

Orcial Ceolin Bortolotto, Thiago Augusto Campos + Show 2 more

Open Access

https://doi.org/10.4025/actasciagron.v38i2.27711

Copy DOI

Abstract

This study aimed to evaluate the influence of the distance from the edge of native forests on the abundance of aphidophagous hoverflies in wheat fields. The study was conducted in four commercial fields in the North of Parana State, Brazil, during the wheat crop season of 2009. Two transects were surveyed parallel to the edge of the forest at two distances: 25 (near) and 525 meters (far) from the edge. The abundance of hoverflies was compared using a χ 2 test (p ≤ 0.05). In total, 1,845 hoverflies adults were collected, which represented 15 species and three genera. The most abundant species was Allograpta exotica (60.43%), followed by Toxomerus dispar (17.78%) and Toxomerus watsoni (7.26%) (Diptera: Syrphidae). An important inference was that all fields showed a higher abundance of aphidophagous hoverflies closer to the edge of the forest (25 m) during the wheat tillering stage. The initial abundance of aphidophagous hoverflies in wheat fields is likely greater near the edge because of the availability of resources in the surrounding forest that enhance hoverfly survival during periods of low aphid infestation.

Highlights

Hoverflies (Diptera: Syrphidae) are notably important insects because they act as pollinators (Jun, Yibo, Jin, Fazhi, & Zhenhai, 2009; Blaauw & Isaacs, 2014) and biological control agents (Irshad, 2014)
The predominant species was A. exotica (58%), which was followed by Pseudodorus clavatus (12%) (Diptera: Syrphidae)
In this study, we found a prevalence of aphidophagous predators in general, which was associated with the aphid abundance, but they were initially more abundant near the hedge forest fragment

Summary

Introduction

Hoverflies (Diptera: Syrphidae) are notably important insects because they act as pollinators (Jun, Yibo, Jin, Fazhi, & Zhenhai, 2009; Blaauw & Isaacs, 2014) and biological control agents (Irshad, 2014). Because of the importance of floral resources to hoverflies, many studies have been conducted to promote the action of this natural enemy in crop fields using landscape management (Hickman & Wratten, 1996; Bokina, 2012; Amaral et al, 2013; Gontijo, Beers, & Snyder, 2013; Martínez-Uña, Martín, Fernández-Quintanilla, & Dorado, 2013; Haenke et al, 2014).

Objectives

Methods

Results