Identification and efficacy of active metabolites of pomegranate fruit peel aqueous extract against sucking pests of rose and their predators

LC ESI Q-TOF metabolomic profiling of pomegranate (Punica granatum Linn.) fruit peel (PFP) aqueous extract was performed to elucidate the possible metabolites present in the PFP, which could be responsible for its acaricidal property against two-spotted spider mites (Tetranychus urticae). Efficacy of PFP aqueous extract has also been evaluated against aphids (Macrosiphum roseiformis), thrips (Scirthothrips dorsalis) as important sucking pests of ornamental rose and for two generalist predators of these pests viz., Coccinella septumpunctata and Orius insidiosus. Toxicity bioassays PFP at 24 h showed highest value of lethal concentrations LC50 for aphids (876 mg/ml) followed by thrips (57 mg/ml) and the least for spider mites (4.5 mg/ml), which shows its high toxicity for spider mites. UHPLC-QTOF/MS analysis has confirmed of several standard and new compounds including presence of genistein, rutin, 2-hydroxy-5-methylquinone, limonene, quercetin 3-O-glucoside, myricetin, kaempferol and alpha-pinene. Kaempferol, quercetin and myricetin confirmed high toxicity towards all the three pests tested. PFP is a biodegradable eco-friendly source that has a promising role in the management of spider mites on roses.