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A definition of the term "acaricide" is presented. It refers to a pesticide which kills mites.

Biological control of spider mites (Acari: Tetranychidae) under dry conditions is a serious problem, which cannot be solved with the currently available strains of predatory mites (Acari: Phytoseiidae). However, there is considerable intraspecific variability in the degree of adaptation to low humidity, allowing the screening for a drought-resistant strain. Due to its plasticity in biological and ecological traits Neoseiulus californicus qualified as a suitable species for strain screening. Egg hatchability, juvenile survival and oviposition rate of eight N. californicus strains were evaluated at three or four humidity levels (ranging from 64.0 to 75.6% r.h. at 25 °C). Strains came from Hérault/France (FR), Tuscany/Italy (FL), Valencia/Spain (SP), La Cruz/Chile (CH), Sicily/Italy (SI), and California/USA (C-BOKU, C-ISZA, CARO). Pronounced intraspecific variation of the traits evaluated at 64.0% r.h. served as a basis to rank the strains and to determine three distinct groups. In the first group (SP, FL, C-ISZA) egg and juvenile survival probability was nearly zero. The second group (FR, CH, C-ARO) was characterized by low egg survival probability (0.14-0.18), but high survival probability of mobile juveniles (0.69-0.82). Strains of the third group had the highest egg and juvenile survival probabilities among the strains evaluated: 0.37 and 0.83 (SI), and 0.38 and 0.96 (C-BOKU), respectively. We conclude that the strains of the latter group are the most promising ones with respect to spider mite control under relatively dry conditions [ABSTRACT FROM AUTHOR]

The potential of using synthetic herbivore-induced plant volatiles (HIPV) (e.g., methyl salicylate, MeSA) as a cultural tool to enhance conservation biological control of mites is being researched in commercially grown hops in Washington State, USA. Compared to unbaited blocks, hop yards baited with controlled release sachet (CRS) dispensers of synthetic MeSA recruited larger (3-5×) populations of spider mite predators: Stethorus spp. (Coleoptera: Coccinellidae), Orius tristicolor (Hemiptera: Anthocoridae), Geocoris pallens (Hemiptera: Geocoridae), Deraeocoris brevis (Hemiptera: Miridae), Chrysopidae, Hemerobiidae, Nabidae, Thripidae. The enhanced community of mite predators controlled spider mite populations in MeSA-baited hops without miticide intervention. All unbaited blocks required at least one miticide for spider mite control. Direct application of natural MeSA (oil of wintergreen) to hop plants contained in canola oil or rosemary/peppermint oil pesticide formulations, resulted in greater attraction of two mite predators (O. tristicolor and Stethorus spp.) to treated than to untreated plants. MeSA-mediated stimulation of the plants to produce predator-attracting volatiles is suggested as the likely mechanism. The use of synthetic or natural versions of HIPV/plant-signaling compounds like MeSA as 'Herbivore-Induced Plant Protection Odors' (HIPPOs), has the potential to provide a novel yet practical strategy for improving the efficacy and reliability of conservation biological control of mites in a variety of agricultural ecosystems. [ABSTRACT FROM AUTHOR]

Dermanyssus gallinae is the most important and common ectoparasite of laying hens in Europe and it is suspected of being a vector of pathogens. Salmonellosis is a major sanitary problem in poultry farms. We performed an in vitro experiment to evaluate the role of D. gallinae as a vector of Salmonella enterica serotype Enteritidis (SE). Two ways of infection of the mites were tested: through the blood meal by artificially engorging mites on contaminated blood, and after cuticular contact by leaving mites on a bacterial coating. The results showed that the mites could be infected via both infection routes. Bacterial multiplication within the mites has also been demonstrated, as well as the transstadial passage of Salmonella from the protonymph to the deutonymph stage, and the transovarial passage associated with a negative effect of SE on Dermanyssus oviposition. Mites have been shown to retransmit bacteria through a blood meal. In order to check whether the ingestion of previously contaminated mites by chicks led to an infection dose sufficient to contaminate birds, sets of 10 mites were orally administered to 1-day-old chicks. Each bird was found to be positive 12 days post-inoculation. Salmonella colonized the intestinal tracts and invaded liver, spleen, and caeca. Therefore, this study demonstrated experimentally that D. gallinae is a vector of SE. The mite may represent a suitable environment for the development of Salmonella and could be an additional factor for the persistence of Salmonella infection between two flocks. This underscores the importance of effective red mite control during the down time following a batch of poultry infected by Salmonella. [ABSTRACT FROM AUTHOR]

The European red mite, Panonychus ulmi (Koch), has assumed the status of major pest in recent years in Himachal Pradesh, India. It is essential that a fresh approach to mite control be undertaken especially by studying its population fluctuation in relation to host plant nutrition. The effect of three levels of N, P, and K, each at the recommended dose (N1, P1, K1), 25% above (N2, P2, K2) and 25% below the recommended dose (N3, P3, K3), plus the untreated control (N0P0K0) was studied on the build-up of P. ulmi populations on potted apple cultivars `Delicious΄ at RHRS, Mashobra, Shimla (2,286 m above sea level). Among ten combinations of NxPxKx, the lowest mite population was recorded at N3P2K2 (i.e., 25% less than recommended N and 25% more than recommended P and K), with 21.9 adults, 29.2 immatures, and 103.2 eggs/leaf. In the control treatment (N0P0K0), 40.0 adults, 44.3 immatures, and 166.3 eggs were obtained. Treatment combination N2P3K3 supported the largest population of 74.8 adults, 91.8 immatures, and 320.9 eggs/Fleaf, significantly different from the other treatments. These results suggested that slight manipulation in the recommended doses of NPK fertilizers can contribute substantially to controlling the abundance of P. ulmi population on apple trees. [ABSTRACT FROM AUTHOR]