Biotic resistance towards Hydrellia egeriae, a biological control agent for the aquatic weed Egeria densa, in South Africa

Moffat, Rosali; van Noort, Simon; Coetzee, Julie A; Hill, Martin P

Title: Biotic resistance towards Hydrellia egeriae, a biological control agent for the aquatic weed Egeria densa, in South Africa
Creator: Moffat, Rosali
Creator: van Noort, Simon
Creator: Coetzee, Julie A
Creator: Hill, Martin P
Subject: To be catalogued
Date Issued: 2024
Date: 2024
Type: text
Type: article
Identifier: http://hdl.handle.net/10962/451299
Identifier: vital:75038
Identifier: http://dx.doi.org/10.17159/2254-8854/2024/a15718
Description: Egeria densa is a submerged aquatic weed that can grow into dense monocultures in rivers and dams in South Africa, which negatively affects ecosystem functioning and services. The biological control agent Hydrellia egeriae Rodrigues-Júnior (Diptera: Ephydridae) was first released against Egeria densa Planchon (Hydrocharitaceae) in South Africa in 2018. Biotic resistance in an introduced range can have negative impacts on the ability of a biological control agent to establish and exert top-down pressure. Dipteran and lepidopteran species that are used as biological control agents are often susceptible to higher levels of parasitism in their introduced range than biological control agents from other insect orders. In addition, ecological analogues that are present in South Africa, make H. egeriae particularly vulnerable to biotic resistance. Considering this, post-release surveys were conducted to investigate if native parasitoids will extend their host range to include H. egeriae. Chaenusa seminervata van Achterberg, C. anervata van Achterberg (Braconidae: Alysiinae: Dacnusini) and Ademon lagarosiphonae van Achterberg (Braconidae: Opiinae) were reared from field-collected H. egeriae pupae, within a year of its release. These braconid parasitoids were previously recorded from a native herbivore, Hydrellia lagarosiphon Deeming (Diptera: Ephydridae).
Format: 6 pages
Format: pdf
Language: English
Relation: African Entomology
Relation: Moffat, R., van Noort, S., Coetzee, J. and Hill, M., 2024. Biotic resistance towards Hydrellia egeriae, a biological control agent for the aquatic weed Egeria densa, in South Africa. African Entomology, 32, pp.1-6
Relation: African Entomology volume 32 number 1 1 6 2024 2254-8854
Rights: Publisher
Rights: Use of this resource is governed by the terms and conditions of the African Entomology Statement (https://www.africanentomology.com/)

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Coetzee, Julie A (Prof)

Hill, Martin Patrick (Distinguished Professor)

RU DST/NRF SARChI for Insects in Sustainable Agricultural Ecosystems

SDG 15. Life On Land

RU Department of Zoology and Entomology

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