Spray Deposition and Efficacy of Four Petroleum-Derived Oils Used Against <I>Tetranychus urticae</I> (Acari: Tetranychidae)

Abstract

Petroleum-derived spray oils (PDSOs) offer an interesting alternative to acaricides to control the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), a key pest of clementine mandarins, Citrus reticulata Blanco. However, there is a lack of knowledge on how these products should be used. In this study, we evaluated the efficacy of four PDSOs (Sunspray Ultrafine, Volck Miscible, Texaco D-C-Tron Plus, and Agroaceite) at five concentrations (0.5, 1.0, 1.5, 2.0, and 3.0%) against eggs, protonymphs, and adults of T. urticae. We also characterized the PDSOs deposition pattern to find out the possible relationship between this factor and efficacy. In general, for all PDSO assayed, the higher the concentration, the higher the coverage, the mean area of impacts and efficacy on T. urticae. The biggest mean area of the impacts corresponded to Texaco D-C-Tron Plus. This PDSO was the most effective one and its efficacy was independent of concentration for concentrations higher than 1.0%. The same applied for concentrations higher than 1.5-2.0% for Agroaceite, Volck Miscible, and Sunspray Ultrafine, with high efficacies against eggs, protonymphs, and adults. PDSOs are highly effective against T. urticae, the use of these products should be encouraged in integrated citrus pest management programs in Spain. The next step will be to ascertain the efficacy under real field conditions.

Green peach aphid [Myzus persicae (Sulzer) (Hemiptera: Aphididae)] control using Brassicaceae ethyl ester oil sprays

“…; Agnello ; Herron and Barchia ; Johnson and Hodgkinson ), with the most recent studies showing effects on two‐spotted spider mite ( Tetranychus urticae Koch) (Chueca et al. ), citrus red mite [ Panonychus citri (McG. )], citrus rust mite ( Phyllocoptruta oleivora Ashmead), leafminer, ( Phyllocnistis citrella Stainton) (Chen et al.…”

Development of models to predict product deposition from coverage obtained on artificial collectors and their practical application

“…Collectors were photographed immediately after application and the images analyzed using the methodology described by Chueca et al (2010) to estimate coverage on each collector, expressed as percentage of area occupied by the impacts against the total area (%). Finally, the average coverage on each collector of each combination of volume and sprayed solution was calculated.…”

“…In addition, it is difficult to generate a good contrast between the droplets and the surface of leaves because of their darkgreen colour. For these reasons, researchers have used small portions of white polyvinyl chloride (PVC) sheets as artificial targets to simulate the behaviour of citrus leaves (Vidal et al, 2003;Chueca et al, 2010;Garcerá et al, 2011) since previous work showed that these collectors did not show statistically significant differences in coverage percentage, number of impacts per square centimeter and mean area of the impacts when compared to citrus leaves (Mercader et al, 1995). Despite this important advantage, PVC collectors are very difficult to handle in the field, because droplets formed on their surface easily slip, as happens on leaves, which changes the apparent distribution of impacts, and their use is often restricted to the laboratory.…”

Acaricides - Biological Profiles, Effects and Uses in Modern Crop Protection

“…At least some modern oils cause a range of cellular disruption leading to rapid insect death (Najar-Rodriguez et al, 2008). PDSO are highly effective against spider mites and eriophyoid mites in various field and greenhouse crops (Agnello et al, 1994;Nicetic et al, 2001;Marčić et al, 2009;Chueca et al, 2010). Beside mineral, plant oils proved to be effective acaricides as well, such as cottonseed oil (Rock & Crabtree, 1987) soybean oil (Lancaster et al, 2002;Moran et al, 2003) and rapeseed oil (Kiss et al, 1996;Marčić et al, 2009).…”

“…On the other side, abamectin and milbemectin, which are also broad-spectrum insecto-acaricides, are considered safe to beneficial arthropods under field conditions due to their short environmental persistance, rapid uptake into treated plants and fast degradation of surface residues (Krämer & Schirmer, 2007). Although beneficials may be killed when treated directly by spray oils or exposed to the vapor phase of essential oils, their short-term residual activity does not severely affect populations of phytoseiid mites and other predators (Chueca et al, 2010;Han et al, 2010).…”