The Effects of Natural Insecticides on the Green Peach Aphid Myzus persicae (Sulzer) and Its Natural Enemies Propylea quatuordecimpunctata (L.) and Aphidius colemani Viereck.

Autor: Lami, Francesco, Burgio, Giovanni, Magagnoli, Serena, Depalo, Laura, Lanzoni, Alberto, Frassineti, Elettra, Marotti, Ilaria, Alpi, Mattia, Mercatante, Dario, Rodriguez-Estrada, Maria Teresa, Dinelli, Giovanni, Masetti, Antonio
Předmět:
Zdroj: Insects (2075-4450); Jul2024, Vol. 15 Issue 7, p556, 15p
Abstrakt: Simple Summary: Botanical insecticides and soaps are frequently considered environmentally friendly and compatible with the biological control of pests because of their purported higher selectivity towards beneficial insects when compared with synthetic insecticides. These claims are, however, only partially backed up by the scientific literature, thus justifying a case-by-case evaluation of botanical insecticides. Here, we tested the efficacy of five botanical insecticides and soaps belonging to different categories (pyrethrins, essential oils, crude plant extracts and insecticidal soaps) on the important aphid pest Myzus persicae (Sulzer) and their selectivity towards two of its biological control agents, the ladybird beetle Propylea quatuordecimpunctata (L.) and the parasitoid Aphidius colemani (Dalman). The pyrethrin-based product was the most effective against aphids but more detrimental to ladybird beetle larvae when compared to the alternatives. Some detrimental effects on ladybird beetles were also caused by white thyme essential oil, sweet orange essential oil and Marseille soap. Additionally, although pyrethrins have a broader spectrum of insecticidal activity compared to most botanical insecticides, they had no significant adverse effect on adult ladybird beetles and parasitoids within aphid mummies, similar to most of the other tested natural products. Botanical insecticides and soaps are frequently proposed as environmentally safer alternatives to synthetic insecticides. However, the efficacy and selectivity of these products are often only partially supported by empirical evidence. Here, we tested the effectiveness of five botanical insecticides, belonging to different categories, on the green peach aphid Myzus persicae (Sulzer) and their selectivity towards two natural enemies, the ladybird beetle Propylea quatuordecimpunctata (L.) and the parasitoid Aphidius colemani (Dalman). White thyme essential oil (EO), sweet orange EO, crude garlic extract and Marseille soap were tested and compared with a pyrethrin-based commercial product. Both direct spray assays and residual contact assays on treated cabbage leaf disks were carried out. The tested products had low efficacy against aphids when compared to pyrethrins but were in general less detrimental to ladybird beetle larvae, meaning that if applied against other pests, they have a lower chance of harming this agent of aphid biocontrol. Some of the products (soap, orange EO) did, however, show direct exposure toxicity toward ladybird larvae, and thyme EO had extensive phytotoxic effects on cabbage leaves, possibly indirectly leading to higher mortality in ladybird adults. These results underline the necessity for case-by-case evaluations of botanical insecticides. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje