Susceptibility of Tetranychus urticae Koch to an ethanol extract of Cnidoscolus aconitifolius leaves under laboratory conditions

Abstract

One of the main pests of commercial rose crops in Colombia is the phytophagous mite Tetranychus urticae Koch. To manage this pest, synthetic chemicals have traditionally been used, some of which are well known to be potentially toxic to the environment and humans. Therefore, alternative strategies for pest management in greenhouse crops have been developed in recent years, including biological control with natural enemies such as parasitoids, predators and entomopathogenic microorganisms as well as chemical control using plant extracts. Such extracts have shown toxicity to insects, which has positioned them as a common alternative in programs of integrated pest management. The objective of this study was to evaluate the effect of an unfractionated ethanolic extract of Cnidoscolus aconitifolius leaves on adult females of T. urticae under laboratory conditions. The extract was chemically characterized by recording its metabolic profile via liquid chromatography coupled to mass spectrometry, along with tentative metabolite identification. The immersion technique and direct application to rose leaves were used to evaluate the effects of seven doses (10–2,000 µg/mL) of the ethanol extract of C. aconitifolius leaves on T. urticae females under laboratory conditions. The mortality and oviposition of individuals were recorded at 24, 48 and 72 h. It was found that the C. aconitifolius leaf extract reduced fertility and increased mortality in a dose-dependent manner. The main metabolites identified included flavonoid- and sesquiterpene-type compounds, in addition to chromone- and xanthone-type compounds as minor constituents with potential acaricidal effects.

Ethanol Extraction of Hyoscyamus niger and Hypericum calycinum Evaluated for Acaricidal Activity against Tetranychus urticae Koch (Acari: Tetranychidae)

“…The results shown in Table 3 indicated that ethanol extracts of H. niger and H. calycinum caused a reduction in the number of eggs laid per female. This is consistent with the results established by Numa et al [40] who reported that application of plant extracts may affect the oviposition of T. urticae females. It was revealed that the number of eggs laid per female decreases when an increasing concentration of a plant extract was applied [41,42].…”

Phenolic profile and antioxidant capacity of Cnidoscolus chayamansa and Cnidoscolus aconitifolius: A review

“…The solvent was removed by rotary evaporation to dryness and the resulting material dried completely in an oven at 25°C. Numa et al (2015) mention that to prepare the soluble extract in ethanol, the C. aconitifolius leaf was dried, ground and macerated for 7 days in a solution of 96% ethanol, changing the solvent daily.…”

Phytochemical profile of cansanção nettle extracts and their bioactivities on cabbage caterpillar

“…bras., Brasília, v.52, n.10, p.841-848, out. 2017 DOI: 10.1590/S0100-204X2017001000003 on the mortality of the adult females of Tetranychus urticae (Numa et al, 2015); and the extracts and oils of C. phyllacanthus exerting a larvicidal effect on the control of Aedes aegypti (Candido et al, 2013). The ethanolic leaf and root extracts and the aqueous root extract caused the larval phase of the cabbage caterpillar to be prolonged, in comparison with the other treatments that also showed differences from one another (Table 2).…”