On the role of sinigrin (mustard oil) in a tritrophic context: plant–aphid–aphidophagous hoverfly

Abstract

1. Plant secondary metabolites can govern prey–predator interactions by altering the diet breadth of predators and sometimes provide an ecological refuge to prey. Brassicaceae plants and their specialist pests can be used as a model system for understanding the role of chemically mediated effects restricting the diet breadth of natural enemies, and consequently the occurrence of enemy‐free space for the specialist pest.2. The objective of the present study was to test the performance of the generalist predator Episyrphus balteatus De Geer (Diptera: Syrphidae) fed on the specialist herbivore Brevicoryne brassicae L.(Homoptera: Aphididae), reared on two different brassica species: black mustard (Brassica nigra), a wild species with high levels of sinigrin; and canola (Brassica napus), a cultivated species without sinigrin.3. The preference and performance of the predator and the performance of the prey were measured. Sinigrin was quantified by high‐performance liquid chromatography in both leaf samples and aphids reared on the two host plants.4. The cabbage aphid performed better on canola than on black mustard. The performance of the predator on this aphid when reared on canola was clearly better than when reared on black mustard. Females had a higher overall preference for cabbage aphids reared on canola than on black mustard.5. The ability of aphids reared on plants with high glucosinolate content to reduce the performance of their generalist predators indicates that the presence of B. nigra may provide enemy‐free space for the cabbage aphid from its predator, a concept that has useful application in the context of biological control for agricultural systems.

Leaf metabolic signatures induced by real and simulated herbivory in black mustard (Brassica nigra)

“…The herb Brassica nigra (Brassicaceae) and its specialist herbivore Pieris brassicae (Lepidoptera: Pieridae) constitute a model system of chemical ecological interactions (Blatt et al 2008; Bruinsma et al 2008; Broekgaarden et al 2011; Amiri-Jami et al 2016; Lucas-Barbosa et al 2016). This system has been used to investigate plant adaptation to multiple stresses (Khaling et al 2015; Kask et al 2016; Papazian et al 2016; Ponzio et al 2017 ).…”

Predatory Insect Species Associated With Some Rosaceous Plants in Edi̇rne (Trakya University Arboretum), Turkey

“…The nests looked like a tent made from old leaves, with only a small pupa in a nest. (1) : individuals collected from the field in larval stage; (2) : collected in pupal stage; (3) : collected in adult stage; (4) : non-herbivorous at all life stages.…”

“…Predatory insects and their associated Rosaceae plants recorded during the study. (1) : individuals collected from the field in larval stage; (2) : collected in pupal stage; (3) : collected in adult stage; (4) : non-herbivorous at all life stages.…”

“…Because of the effective predatory feature of their larvae, these species are important in biocontrol of aphids (Zeki and Kılınçer 1990, Cowgill et al 1993, Putra and Yasuda 2006 (Dyer 1995, Amiri-Jami et al 2015. According to a study carried out by Vanhaelen et al (2002), specialist aphids feed on their preferred plant if it is rich in its specific metabolites.…”

Aphid suitability for the predatory hoverfly Episyrphus balteatus altered with elevating atmospheric CO2 and sinigrin

“…As a result, other factors such as prey toxicity, size and relative composition are probably more important (e.g. Chaplin‐Kramer et al ; Kos et al ; Amiri‐Jami & Sadeghi‐Namaghi ; Amiri‐Jami et al ), and indeed the suitability of insect prey for insect predators is thought mainly to be determined by toxin content (Hodek ; White et al ). Rising levels of atmospheric CO 2 can enhance the concentration of allelochemicals in plant tissues (Scriber & Slansky ).…”