BACKGROUND: Tetranychus urticae Koch, is a polyphagous and damaging pest, presenting several resistant populations worldwide. Among new and more environmentally friendly control tools, botanical pesticides represent a valuable alternative to synthetic ones within integrated pest management strategies. Accordingly, we investigated the lethal and sublethal effects of carlina oxide isolated from Carlina acaulis (Asteraceae) roots on T. urticae and its natural enemy, the predatory mite, Neoseiulus californicus (McGregor).RESULTS: Carlina oxide (98.7% pure compound) was used for acaricidal tests on eggs, nymphs, and adult females of T. urticae (concentrations of 312.5, 625, 1250, 2500 and 5000 μL L⁻¹), and eggs and females of N. californicus (1250 and 5000 μL L⁻¹ on eggs and females, respectively). Behavioral two‐choice tests were also conducted on phytoseiid females. Carlina oxide toxicity was higher on T. urticae females than nymphs (median lethal dose 1145 and 1825 μL L⁻¹, respectively), whereas egg mortality and mean hatching time were significantly affected by all tested concentrations. A decreasing daily oviposition rate for T. urticae was recorded with concentrations ranging from 625 to 5000 μL L⁻¹, whereas negative effects on the population growth rate were recorded only with the three higher concentrations (1250, 2500 and 5000 μL L⁻¹). No toxic effect on N. californicus females was found, but a strong repellent activity lasting for 48 h from application was recorded.CONCLUSION: Carlina oxide reduced longevity and fecundity of T. urticae adults, but not of N. californicus. This selective property allows us to propose it as a novel active ingredient of ecofriendly acaricides for T. urticae management. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Growing demands for environmentally safe and sustainable pest management have increased interest in biopesticides as alternatives to synthetic chemical pesticides. This review presents the current status of bioacaricides, defined as commercial biopesticide products based on microorganisms (microbial acaricides) and biologically active substances of microbial, plant or animal origin (biochemicals and semiochemicals) used in crop protection against spider mites (Tetranychidae) and other plant-feeding mites. The most important microbial bioacaricides are mycopesticides, which are products manufactured from living propagules of Beauveria bassiana s.l. and several other acaropathogenic fungi. Products based on avermectins and milbemycins, secondary metabolites of actinomycetes, are well-known examples of biochemicals of microbial origin. Among the biochemicals of plant origin, the most widely used to date have been the products based on pyrethrum—obtained from the Dalmatian daisy, Tanacetum cinerariifolium (Asteraceae)—and azadirachtin, obtained from the Indian neem tree, Azadirachta indica (Meliaceae). In recent years, products based on essential oils from aromatic plants belonging to the families Lamiaceae, Myrtaceae, Rutaceae and others have also gained increasing importance in the market. Special emphasis in this review is given to the compatibility of bioacaricides with predatory mites of the family Phytoseiidae as biological control agents used in the integrated management of plant-feeding mites.

Neoseiulus fallacis (Garman) is a broadly commercialised phytoseiid mite used in Integrated Pest Management (IPM) programmes especially in northern and southern America. However, its taxonomic status was, until now, equivocal because no redescription based on type material had ever been made. The authors redescribe N. fallacis from type material in Garman’s collection, designating the lectotype and paralectotypes for the species. Moreover, a new species of the fallacis complex, discovered among the fallacis type material, is described and named N. garmani sp. nov. in honour of Philip Garman.

The tomato russet mite (TRM), Aculops lycopersici, is a destructive pest of tomato crops worldwide. It poses a significant challenge to growers in both greenhouse and open-field conditions. Traditional chemical control methods are often ineffective, promote resistance, and have negative environmental impacts. This has prompted the search for alternative strategies, such as biological control and eco-friendly botanical pesticides. In this study, we evaluated the acaricidal effects of essential oils (EOs) extracted from three officinal plants, Origanum vulgare L., Salvia rosmarinus Spenn., and Salvia officinalis L., cultivated using precision aromatic crop (PAC) techniques. Their efficacy was evaluated against A. lycopersici under laboratory conditions. The chemical composition of the EOs was determined by solid-phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC-MS). The dominant component of O. vulgare EO was carvacrol (83.42%), followed by ρ-cymene (3.06%), and γ-terpinene (2.93%). In S. rosmarinus, α-pinene (28.0%), 1,8-cineole (11.00%), and borneol (7.72%) were the major components. S. officinalis EO was characterized by high levels of 1,8-cineole (27.67%), camphor (21.91%), and crisantenone (12.87%). We tested multiple concentrations (320–5000 μL L−¹) and exposure times (1–4 days) to assess mite mortality. The results revealed both dose- and time-dependent toxic activity, with significant differences among EOs. O. vulgare EO was the most toxic, causing 90% mortality at 0.5% (w/v) concentration after 4 days. S. rosmatinus and S. officinalis EOs had more limited effects, with 46% and 42% mortality, respectively. Lethal concentration (LC₅₀) values were 2.23 mL L−¹ (95% CI: 1.74–3.05) for O. vulgare, 5.84 mL L−¹ (95% CI: 3.28–22.29) for S. rosmarinus, and 6.01 mL L−¹ (95% CI: 2.63–261.60) for S. officinalis. These results indicate that O. vulgare EO shows efficacy comparable to commercially available botanical pesticides. Our findings support the potential of O. vulgare EO as a viable alternative for the control of A. lycopersici, contributing to integrated pest management (IPM) strategies.

Tetranychus urticae is the most important pest on different crops worldwide. Search for endemic phytoseiid mites co-occurring with the above pest, which might be good candidates as biocontrol agents, represents the policy followed by most scientists in recent years. The aim of the present work was to assess the various biological and demographic parameters of Neoseiulus longilaterus, associated with T. urticae on weeds, in laboratory conditions using the latter tetranychid and pollen of Oxalis pes-caprae as food. The results showed a better performance of the predator on the prey as regards the postembryonic development (7.63 and 8.18 days for prey and pollen respectively) and the demographic parameters (rm 0.158 and 0.102, Ro 26.89 and 18.76, DT 4.39 and 6.78 for T. urticae and Oxalis respectively). Our data shows that N. longilaterus have similar traits with some phytoseiid species belonging to type II selective predators, but also with some others included within type III generalist predators. As a matter of fact, it can be considered an interesting biocontrol agent towards T. urticae, able also to develop on alternative foods as the pollen of Oxalis.

Considerations on systematics of the Phytoseiidae (Acari: Mesostigmata), with definition of a new species group and description of a new species